diff --git a/src/common/Utilities/EventProcessor.cpp b/src/common/Utilities/EventProcessor.cpp
index 3943a09b8..3ee951604 100644
--- a/src/common/Utilities/EventProcessor.cpp
+++ b/src/common/Utilities/EventProcessor.cpp
@@ -75,7 +75,7 @@ void EventProcessor::Update(uint32 p_time)
 
         // Reschedule non deletable events to be checked at
         // the next update tick
-        AddEvent(event, CalculateTime(1), false, 0);
+        AddEvent(event, CalculateTime(1), false);
     }
 }
 
@@ -133,13 +133,13 @@ void EventProcessor::CancelEventGroup(uint8 group)
     }
 }
 
-void EventProcessor::AddEvent(BasicEvent* Event, uint64 e_time, bool set_addtime, uint8 eventGroup)
+void EventProcessor::AddEvent(BasicEvent* Event, uint64 e_time, bool set_addtime /*= true*/, uint8 eventGroup /*= 0*/)
 {
     if (set_addtime)
         Event->m_addTime = m_time;
     Event->m_execTime = e_time;
     Event->m_eventGroup = eventGroup;
-    m_events.insert(std::pair<uint64, BasicEvent*>(e_time, Event));
+    m_events.emplace(e_time, Event);
 }
 
 void EventProcessor::ModifyEventTime(BasicEvent* event, Milliseconds newTime)
@@ -151,7 +151,7 @@ void EventProcessor::ModifyEventTime(BasicEvent* event, Milliseconds newTime)
 
         event->m_execTime = newTime.count();
         m_events.erase(itr);
-        m_events.insert(std::pair<uint64, BasicEvent*>(newTime.count(), event));
+        m_events.emplace(newTime.count(), event);
         break;
     }
 }
diff --git a/src/common/Utilities/EventProcessor.h b/src/common/Utilities/EventProcessor.h
index 3e7896bb3..f114e0f83 100644
--- a/src/common/Utilities/EventProcessor.h
+++ b/src/common/Utilities/EventProcessor.h
@@ -100,20 +100,19 @@ class EventProcessor
 
         void Update(uint32 p_time);
         void KillAllEvents(bool force);
-        void AddEvent(BasicEvent* Event, uint64 e_time, bool set_addtime = true) { AddEvent(Event, e_time, set_addtime, 0); };
-        void AddEvent(BasicEvent* Event, uint64 e_time, bool set_addtime, uint8 eventGroup);
+
+        void AddEvent(BasicEvent* Event, uint64 e_time, bool set_addtime = true, uint8 eventGroup = 0);
         template<typename T>
-        is_lambda_event<T> AddEvent(T&& event, Milliseconds e_time, bool set_addtime = true) { AddEvent(new LambdaBasicEvent<T>(std::move(event)), e_time, set_addtime); }
-        void AddEventAtOffset(BasicEvent* event, Milliseconds offset) { AddEvent(event, CalculateTime(offset.count()), true, 0); }
-        void AddEventAtOffset(BasicEvent* event, Milliseconds offset, Milliseconds offset2) { AddEvent(event, CalculateTime(randtime(offset, offset2).count()), true, false); }
+        is_lambda_event<T> AddEvent(T&& event, Milliseconds e_time, bool set_addtime = true, uint8 eventGroup = 0) { AddEvent(new LambdaBasicEvent<T>(std::move(event)), e_time.count(), set_addtime, eventGroup); }
+
+        void AddEventAtOffset(BasicEvent* event, Milliseconds offset, uint8 eventGroup = 0) { AddEvent(event, CalculateTime(offset.count()), true, eventGroup); }
         template<typename T>
-        is_lambda_event<T> AddEventAtOffset(T&& event, Milliseconds offset, uint8 eventGroup) { AddEvent(new LambdaBasicEvent<T>(std::move(event)), CalculateTime(offset.count()), true, eventGroup); };
+        is_lambda_event<T> AddEventAtOffset(T&& event, Milliseconds offset, uint8 eventGroup = 0) { AddEventAtOffset(new LambdaBasicEvent<T>(std::move(event)), offset, eventGroup); };
+
+        void AddEventAtOffset(BasicEvent* event, Milliseconds offset, Milliseconds offset2, uint8 eventGroup = 0) { AddEvent(event, CalculateTime(randtime(offset, offset2).count()), true, eventGroup); }
         template<typename T>
-        is_lambda_event<T> AddEventAtOffset(T&& event, Milliseconds offset, Milliseconds offset2, uint8 eventGroup) { AddEvent(new LambdaBasicEvent<T>(std::move(event)), CalculateTime(randtime(offset, offset2).count()), true, eventGroup); };
-        template<typename T>
-        is_lambda_event<T> AddEventAtOffset(T&& event, Milliseconds offset) { AddEventAtOffset(new LambdaBasicEvent<T>(std::move(event)), offset); }
-        template<typename T>
-        is_lambda_event<T> AddEventAtOffset(T&& event, Milliseconds offset, Milliseconds offset2) { AddEventAtOffset(new LambdaBasicEvent<T>(std::move(event)), offset, offset2); }
+        is_lambda_event<T> AddEventAtOffset(T&& event, Milliseconds offset, Milliseconds offset2, uint8 eventGroup = 0) { AddEventAtOffset(new LambdaBasicEvent<T>(std::move(event)), offset, offset2, eventGroup); };
+
         void ModifyEventTime(BasicEvent* event, Milliseconds newTime);
         [[nodiscard]] uint64 CalculateTime(uint64 t_offset) const;
 
@@ -121,6 +120,7 @@ class EventProcessor
         [[nodiscard]] uint64 CalculateQueueTime(uint64 delay) const;
 
         void CancelEventGroup(uint8 group);
+        bool HaveEventList() const { return !m_events.empty(); }
 
     protected:
         uint64 m_time{0};
diff --git a/src/server/game/Battlegrounds/BattlegroundQueue.cpp b/src/server/game/Battlegrounds/BattlegroundQueue.cpp
index 81832437b..f34d833c4 100644
--- a/src/server/game/Battlegrounds/BattlegroundQueue.cpp
+++ b/src/server/game/Battlegrounds/BattlegroundQueue.cpp
@@ -366,7 +366,7 @@ void BattlegroundQueue::RemovePlayer(ObjectGuid guid, bool decreaseInvitedCount)
 
 void BattlegroundQueue::AddEvent(BasicEvent* Event, uint64 e_time)
 {
-    m_events.AddEvent(Event, m_events.CalculateTime(e_time));
+    m_events.AddEventAtOffset(Event, Milliseconds(e_time));
 }
 
 bool BattlegroundQueue::IsPlayerInvitedToRatedArena(ObjectGuid pl_guid)
diff --git a/src/server/game/Entities/Creature/Creature.cpp b/src/server/game/Entities/Creature/Creature.cpp
index 451975e1b..4b18aa2e9 100644
--- a/src/server/game/Entities/Creature/Creature.cpp
+++ b/src/server/game/Entities/Creature/Creature.cpp
@@ -2159,12 +2159,12 @@ void Creature::Respawn(bool force)
     }
 }
 
-void Creature::ForcedDespawn(uint32 timeMSToDespawn, Seconds forceRespawnTimer)
+void Creature::ForcedDespawn(Milliseconds timeMSToDespawn, Seconds forceRespawnTimer)
 {
-    if (timeMSToDespawn)
+    if (timeMSToDespawn > 0ms)
     {
         ForcedDespawnDelayEvent* pEvent = new ForcedDespawnDelayEvent(*this, forceRespawnTimer);
-        m_Events.AddEvent(pEvent, m_Events.CalculateTime(timeMSToDespawn));
+        m_Events.AddEventAtOffset(pEvent, timeMSToDespawn);
         return;
     }
 
@@ -2182,9 +2182,9 @@ void Creature::ForcedDespawn(uint32 timeMSToDespawn, Seconds forceRespawnTimer)
 void Creature::DespawnOrUnsummon(Milliseconds msTimeToDespawn /*= 0ms*/, Seconds forcedRespawnTimer /*= 0s*/)
 {
     if (TempSummon* summon = this->ToTempSummon())
-        summon->UnSummon(msTimeToDespawn.count());
+        summon->UnSummon(msTimeToDespawn);
     else
-        ForcedDespawn(msTimeToDespawn.count(), forcedRespawnTimer);
+        ForcedDespawn(msTimeToDespawn, forcedRespawnTimer);
 }
 
 void Creature::DespawnOnEvade(Seconds respawnDelay)
@@ -2464,7 +2464,7 @@ void Creature::CallAssistance(Unit* target /*= nullptr*/)
                     e->AddAssistant((*assistList.begin())->GetGUID());
                     assistList.pop_front();
                 }
-                m_Events.AddEvent(e, m_Events.CalculateTime(sWorld->getIntConfig(CONFIG_CREATURE_FAMILY_ASSISTANCE_DELAY)));
+                m_Events.AddEventAtOffset(e, Milliseconds(sWorld->getIntConfig(CONFIG_CREATURE_FAMILY_ASSISTANCE_DELAY)));
             }
         }
     }
@@ -3762,7 +3762,7 @@ void Creature::ModifyThreatPercentTemp(Unit* victim, int32 percent, Milliseconds
         }
 
         TemporaryThreatModifierEvent* pEvent = new TemporaryThreatModifierEvent(*this, victim->GetGUID(), currentThreat);
-        m_Events.AddEvent(pEvent, m_Events.CalculateTime(duration.count()));
+        m_Events.AddEventAtOffset(pEvent, duration);
     }
 }
 
diff --git a/src/server/game/Entities/Creature/Creature.h b/src/server/game/Entities/Creature/Creature.h
index 93baba17a..1ea560045 100644
--- a/src/server/game/Entities/Creature/Creature.h
+++ b/src/server/game/Entities/Creature/Creature.h
@@ -505,7 +505,7 @@ protected:
     bool IsAlwaysDetectableFor(WorldObject const* seer) const override;
 
 private:
-    void ForcedDespawn(uint32 timeMSToDespawn = 0, Seconds forcedRespawnTimer = 0s);
+    void ForcedDespawn(Milliseconds timeMSToDespawn = 0ms, Seconds forcedRespawnTimer = 0s);
 
     [[nodiscard]] bool CanPeriodicallyCallForAssistance() const;
 
diff --git a/src/server/game/Entities/Creature/TemporarySummon.cpp b/src/server/game/Entities/Creature/TemporarySummon.cpp
index 0b0c17a1e..76170ff7e 100644
--- a/src/server/game/Entities/Creature/TemporarySummon.cpp
+++ b/src/server/game/Entities/Creature/TemporarySummon.cpp
@@ -284,13 +284,12 @@ void TempSummon::SetTempSummonType(TempSummonType type)
     m_type = type;
 }
 
-void TempSummon::UnSummon(uint32 msTime)
+void TempSummon::UnSummon(Milliseconds msTime)
 {
-    if (msTime)
+    if (msTime > 0ms)
     {
         ForcedUnsummonDelayEvent* pEvent = new ForcedUnsummonDelayEvent(*this);
-
-        m_Events.AddEvent(pEvent, m_Events.CalculateTime(msTime));
+        m_Events.AddEventAtOffset(pEvent, msTime);
         return;
     }
 
diff --git a/src/server/game/Entities/Creature/TemporarySummon.h b/src/server/game/Entities/Creature/TemporarySummon.h
index 72a199327..f3a285c60 100644
--- a/src/server/game/Entities/Creature/TemporarySummon.h
+++ b/src/server/game/Entities/Creature/TemporarySummon.h
@@ -44,7 +44,7 @@ public:
     void Update(uint32 time) override;
     virtual void InitStats(uint32 lifetime);
     virtual void InitSummon();
-    virtual void UnSummon(uint32 msTime = 0);
+    virtual void UnSummon(Milliseconds msTime = 0ms);
     void UpdateObjectVisibilityOnCreate() override;
     void RemoveFromWorld() override;
     void SetTempSummonType(TempSummonType type);
@@ -133,4 +133,5 @@ public:
 private:
     TempSummon& m_owner;
 };
+
 #endif
diff --git a/src/server/game/Entities/Totem/Totem.cpp b/src/server/game/Entities/Totem/Totem.cpp
index db4fae0e6..3bf8a5517 100644
--- a/src/server/game/Entities/Totem/Totem.cpp
+++ b/src/server/game/Entities/Totem/Totem.cpp
@@ -119,11 +119,11 @@ void Totem::InitSummon()
     }
 }
 
-void Totem::UnSummon(uint32 msTime)
+void Totem::UnSummon(Milliseconds msTime)
 {
-    if (msTime)
+    if (msTime > 0ms)
     {
-        m_Events.AddEvent(new ForcedUnsummonDelayEvent(*this), m_Events.CalculateTime(msTime));
+        m_Events.AddEventAtOffset(new ForcedUnsummonDelayEvent(*this), msTime);
         return;
     }
 
diff --git a/src/server/game/Entities/Totem/Totem.h b/src/server/game/Entities/Totem/Totem.h
index 5265435d5..27ccc12bb 100644
--- a/src/server/game/Entities/Totem/Totem.h
+++ b/src/server/game/Entities/Totem/Totem.h
@@ -55,7 +55,7 @@ public:
     void Update(uint32 time) override;
     void InitStats(uint32 duration) override;
     void InitSummon() override;
-    void UnSummon(uint32 msTime = 0) override;
+    void UnSummon(Milliseconds msTime = 0ms) override;
     uint32 GetSpell(uint8 slot = 0) const { return m_spells[slot]; }
     uint32 GetTotemDuration() const { return m_duration; }
     void SetTotemDuration(uint32 duration) { m_duration = duration; }
diff --git a/src/server/game/Entities/Unit/Unit.cpp b/src/server/game/Entities/Unit/Unit.cpp
index afc90e1a4..54b914833 100644
--- a/src/server/game/Entities/Unit/Unit.cpp
+++ b/src/server/game/Entities/Unit/Unit.cpp
@@ -11071,7 +11071,7 @@ int32 Unit::DealHeal(Unit* healer, Unit* victim, uint32 addhealth)
     return gain;
 }
 
-bool RedirectSpellEvent::Execute(uint64  /*e_time*/, uint32  /*p_time*/)
+bool RedirectSpellEvent::Execute(uint64 /*e_time*/, uint32 /*p_time*/)
 {
     if (Unit* auraOwner = ObjectAccessor::GetUnit(_self, _auraOwnerGUID))
     {
@@ -19572,7 +19572,7 @@ void Unit::ExitVehicle(Position const* /*exitPosition*/)
     }
 }
 
-bool VehicleDespawnEvent::Execute(uint64  /*e_time*/, uint32  /*p_time*/)
+bool VehicleDespawnEvent::Execute(uint64 /*e_time*/, uint32 /*p_time*/)
 {
     Position pos = _self;
     _self.MovePositionToFirstCollision(pos, 20.0f, M_PI);
@@ -19699,7 +19699,7 @@ void Unit::_ExitVehicle(Position const* exitPosition)
             setDeathState(DeathState::JustDied);
         // If for other reason we as minion are exiting the vehicle (ejected, master dismounted) - unsummon
         else
-            ToTempSummon()->UnSummon(2000); // Approximation
+            ToTempSummon()->UnSummon(2s); // Approximation
     }
 
     if (player)
@@ -20086,7 +20086,7 @@ class AuraMunchingQueue : public BasicEvent
 public:
     AuraMunchingQueue(Unit& owner, ObjectGuid targetGUID, int32 basePoints, uint32 spellId, AuraEffect* aurEff, AuraType auraType) : _owner(owner), _targetGUID(targetGUID), _basePoints(basePoints), _spellId(spellId), _aurEff(aurEff), _auraType(auraType) { }
 
-    bool Execute(uint64 /*eventTime*/, uint32 /*updateTime*/) override
+    bool Execute(uint64 /*e_time*/, uint32 /*p_time*/) override
     {
         if (_owner.IsInWorld() && _owner.FindMap())
             if (Unit* target = ObjectAccessor::GetUnit(_owner, _targetGUID))
diff --git a/src/server/game/Spells/Spell.cpp b/src/server/game/Spells/Spell.cpp
index 4ae8bfca4..644cce3b6 100644
--- a/src/server/game/Spells/Spell.cpp
+++ b/src/server/game/Spells/Spell.cpp
@@ -2392,7 +2392,7 @@ void Spell::AddUnitTarget(Unit* target, uint32 effectMask, bool checkIfValid /*=
             targetInfo.reflectResult = SPELL_MISS_PARRY;
 
         // Increase time interval for reflected spells by 1.5
-        m_caster->m_Events.AddEvent(new ReflectEvent(m_caster, targetInfo.targetGUID, m_spellInfo), m_caster->m_Events.CalculateTime(targetInfo.timeDelay));
+        m_caster->m_Events.AddEventAtOffset(new ReflectEvent(m_caster, targetInfo.targetGUID, m_spellInfo), Milliseconds(targetInfo.timeDelay));
         targetInfo.timeDelay += targetInfo.timeDelay >> 1;
 
         m_spellFlags |= SPELL_FLAG_REFLECTED;
@@ -3439,7 +3439,7 @@ SpellCastResult Spell::prepare(SpellCastTargets const* targets, AuraEffect const
 
     // create and add update event for this spell
     _spellEvent = new SpellEvent(this);
-    m_caster->m_Events.AddEvent(_spellEvent, m_caster->m_Events.CalculateTime(1));
+    m_caster->m_Events.AddEventAtOffset(_spellEvent, 1ms);
 
     if (sDisableMgr->IsDisabledFor(DISABLE_TYPE_SPELL, m_spellInfo->Id, m_caster))
     {
@@ -8166,7 +8166,7 @@ bool SpellEvent::IsDeletable() const
     return m_Spell->IsDeletable();
 }
 
-bool ReflectEvent::Execute(uint64  /*e_time*/, uint32  /*p_time*/)
+bool ReflectEvent::Execute(uint64 /*e_time*/, uint32 /*p_time*/)
 {
     Unit* target = ObjectAccessor::GetUnit(*_caster, _targetGUID);
     if (target && _caster->IsInMap(target))
diff --git a/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockDepths/instance_blackrock_depths.cpp b/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockDepths/instance_blackrock_depths.cpp
index 243d6e71c..fd18069ca 100644
--- a/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockDepths/instance_blackrock_depths.cpp
+++ b/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockDepths/instance_blackrock_depths.cpp
@@ -606,7 +606,7 @@ public:
                     if (Creature* argelmach = instance->GetCreature(ArgelmachGUID))
                     {
                         argelmach->HandleEmoteCommand(EMOTE_ONESHOT_SHOUT);
-                        argelmach->m_Events.AddEvent(new RestoreAttack(argelmach), argelmach->m_Events.CalculateTime(3000));
+                        argelmach->m_Events.AddEventAtOffset(new RestoreAttack(argelmach), 3s);
 
                         for (ObjectGuid const& argelmachAddGUID : ArgelmachAdds)
                         {
diff --git a/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockSpire/boss_the_beast.cpp b/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockSpire/boss_the_beast.cpp
index 80b4a6776..b08470c02 100644
--- a/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockSpire/boss_the_beast.cpp
+++ b/src/server/scripts/EasternKingdoms/BlackrockMountain/BlackrockSpire/boss_the_beast.cpp
@@ -157,8 +157,8 @@ public:
                                     orc->AI()->Talk(SAY_BLACKHAND_DOOMED);
                                 }
 
-                                orc->m_Events.AddEvent(new OrcMoveEvent(orc), me->m_Events.CalculateTime(3 * IN_MILLISECONDS));
-                                orc->m_Events.AddEvent(new OrcDeathEvent(orc), me->m_Events.CalculateTime(9 * IN_MILLISECONDS));
+                                orc->m_Events.AddEventAtOffset(new OrcMoveEvent(orc), 3s);
+                                orc->m_Events.AddEventAtOffset(new OrcDeathEvent(orc), 9s);
                             }
                         }
                     }
diff --git a/src/server/scripts/EasternKingdoms/ScarletEnclave/chapter5.cpp b/src/server/scripts/EasternKingdoms/ScarletEnclave/chapter5.cpp
index 1ec9da6c2..bf307fe0c 100644
--- a/src/server/scripts/EasternKingdoms/ScarletEnclave/chapter5.cpp
+++ b/src/server/scripts/EasternKingdoms/ScarletEnclave/chapter5.cpp
@@ -473,7 +473,7 @@ public:
             if (battleStarted != ENCOUNTER_STATE_FIGHT)
                 return;
 
-            me->m_Events.AddEvent(new DelayedSummonEvent(me, creature->GetEntry(), *creature), me->m_Events.CalculateTime(3000));
+            me->m_Events.AddEventAtOffset(new DelayedSummonEvent(me, creature->GetEntry(), *creature), 3s);
             if (creature->GetEntry() >= NPC_RAMPAGING_ABOMINATION)
             {
                 --scourgeRemaining;
diff --git a/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_felmyst.cpp b/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_felmyst.cpp
index 29bf02409..04fa2023d 100644
--- a/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_felmyst.cpp
+++ b/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_felmyst.cpp
@@ -319,9 +319,10 @@ struct boss_felmyst : public BossAI
                 break;
             case POINT_LANE:
                 Talk(EMOTE_BREATH);
-                me->m_Events.AddEventAtOffset([&] {
+                me->m_Events.AddEventAtOffset([this]()
+                {
                     for (uint8 i = 0; i < 16; ++i)
-                        me->m_Events.AddEvent(new CorruptTriggers(me, _currentLane), me->m_Events.CalculateTime(i*250));
+                        me->m_Events.AddEventAtOffset(new CorruptTriggers(me, _currentLane), Milliseconds(i * 250));
                 }, 5s);
 
                 me->m_Events.AddEventAtOffset([&] {
diff --git a/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_kiljaeden.cpp b/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_kiljaeden.cpp
index f48af4456..af4a14d7d 100644
--- a/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_kiljaeden.cpp
+++ b/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_kiljaeden.cpp
@@ -554,7 +554,7 @@ struct boss_kiljaeden : public BossAI
             summon->SetDisableGravity(true);
             summon->CastSpell(summon, SPELL_ARMAGEDDON_VISUAL, true);
             summon->SetPosition(summon->GetPositionX(), summon->GetPositionY(), summon->GetPositionZ() + 20.0f, 0.0f);
-            summon->m_Events.AddEvent(new CastArmageddon(summon), summon->m_Events.CalculateTime(6000));
+            summon->m_Events.AddEventAtOffset(new CastArmageddon(summon), 6s);
             summon->DespawnOrUnsummon(randtime(8s, 10s));
         }
     }
@@ -787,8 +787,8 @@ struct npc_kalecgos_kj : public NullCreatureAI
         case EVENT_SCENE_05:
             if (Creature* first = me->SummonCreature(NPC_SHATTERED_SUN_SOLDIER, 1729.48f, 640.49f, 28.06f, 3.49f))
             {
-                first->m_Events.AddEvent(new MoveDelayed(first, 1718.70f, 607.78f, 28.06f, 2.323f), first->m_Events.CalculateTime(5000));
-                first->m_Events.AddEvent(new FixOrientation(first), first->m_Events.CalculateTime(12000));
+                first->m_Events.AddEventAtOffset(new MoveDelayed(first, 1718.70f, 607.78f, 28.06f, 2.323f), 5s);
+                first->m_Events.AddEventAtOffset(new FixOrientation(first), 12s);
                 for (uint8 i = 0; i < 9; ++i)
                     if (Creature* follower = me->SummonCreature(NPC_SHATTERED_SUN_SOLDIER, 1729.48f + 5 * cos(i * 2.0f * M_PI / 9), 640.49f + 5 * std::sin(i * 2.0f * M_PI / 9), 28.06f, 3.49f))
                         follower->GetMotionMaster()->MoveFollow(first, 3.0f, follower->GetAngle(first));
@@ -798,8 +798,8 @@ struct npc_kalecgos_kj : public NullCreatureAI
         case EVENT_SCENE_06:
             if (Creature* first = me->SummonCreature(NPC_SHATTERED_SUN_SOLDIER, 1729.48f, 640.49f, 28.06f, 3.49f))
             {
-                first->m_Events.AddEvent(new MoveDelayed(first, 1678.69f, 649.27f, 28.06f, 5.46f), first->m_Events.CalculateTime(5000));
-                first->m_Events.AddEvent(new FixOrientation(first), first->m_Events.CalculateTime(14500));
+                first->m_Events.AddEventAtOffset(new MoveDelayed(first, 1678.69f, 649.27f, 28.06f, 5.46f), 5s);
+                first->m_Events.AddEventAtOffset(new FixOrientation(first), 14500ms);
                 for (uint8 i = 0; i < 9; ++i)
                     if (Creature* follower = me->SummonCreature(NPC_SHATTERED_SUN_SOLDIER, 1729.48f + 5 * cos(i * 2.0f * M_PI / 9), 640.49f + 5 * std::sin(i * 2.0f * M_PI / 9), 28.06f, 3.49f))
                         follower->GetMotionMaster()->MoveFollow(first, 3.0f, follower->GetAngle(first));
diff --git a/src/server/scripts/Kalimdor/CavernsOfTime/TheBlackMorass/the_black_morass.cpp b/src/server/scripts/Kalimdor/CavernsOfTime/TheBlackMorass/the_black_morass.cpp
index e0114b616..a513a41b7 100644
--- a/src/server/scripts/Kalimdor/CavernsOfTime/TheBlackMorass/the_black_morass.cpp
+++ b/src/server/scripts/Kalimdor/CavernsOfTime/TheBlackMorass/the_black_morass.cpp
@@ -199,19 +199,19 @@ struct npc_medivh_bm : public ScriptedAI
                 events.ScheduleEvent(EVENT_OUTRO_3, 2s);
                 break;
             case EVENT_OUTRO_3:
-                SummonOrcs(-2046.158f, -3.0f, 37s, 30000, true);
+                SummonOrcs(-2046.158f, -3.0f, 37s, 30s, true);
                 events.ScheduleEvent(EVENT_OUTRO_4, 2s);
                 break;
             case EVENT_OUTRO_4:
-                SummonOrcs(-2055.97f, -2.0f, 33s, 28000, false);
+                SummonOrcs(-2055.97f, -2.0f, 33s, 28s, false);
                 events.ScheduleEvent(EVENT_OUTRO_5, 2s);
                 break;
             case EVENT_OUTRO_5:
-                SummonOrcs(-2064.0f, -1.5f, 29s, 26000, false);
+                SummonOrcs(-2064.0f, -1.5f, 29s, 26s, false);
                 events.ScheduleEvent(EVENT_OUTRO_6, 2s);
                 break;
             case EVENT_OUTRO_6:
-                SummonOrcs(-2074.35f, -0.1f, 26s, 24000, false);
+                SummonOrcs(-2074.35f, -0.1f, 26s, 24s, false);
                 events.ScheduleEvent(EVENT_OUTRO_7, 7s);
                 break;
             case EVENT_OUTRO_7:
@@ -228,14 +228,14 @@ struct npc_medivh_bm : public ScriptedAI
         }
     }
 
-    void SummonOrcs(float x, float y, Milliseconds duration, uint32 homeTime, bool first)
+    void SummonOrcs(float x, float y, Milliseconds duration, Milliseconds homeTime, bool first)
     {
         for (uint8 i = 0; i < 6; ++i)
         {
             if (Creature* cr = me->SummonCreature(NPC_SHADOW_COUNCIL_ENFORCER, -2091.731f, 7133.083f - 3.0f * i, 34.589f, 0.0f))
             {
                 cr->GetMotionMaster()->MovePoint(0, (first && i == 3) ? x + 2.0f : x, cr->GetPositionY() + y, cr->GetMapHeight(x, cr->GetPositionY() + y, cr->GetPositionZ(), true));
-                cr->m_Events.AddEvent(new NpcRunToHome(*cr), cr->m_Events.CalculateTime(homeTime + urand(0, 2000)));
+                cr->m_Events.AddEventAtOffset(new NpcRunToHome(*cr), homeTime + randtime(0ms, 2s));
                 cr->DespawnOrUnsummon(duration + randtime(0ms, 2s));
             }
         }
diff --git a/src/server/scripts/Kalimdor/zone_silithus.cpp b/src/server/scripts/Kalimdor/zone_silithus.cpp
index dddcb2cf4..7bfd005eb 100644
--- a/src/server/scripts/Kalimdor/zone_silithus.cpp
+++ b/src/server/scripts/Kalimdor/zone_silithus.cpp
@@ -1174,7 +1174,7 @@ public:
                 summons->SetLootRecipient(player);
                 summons->CastSpell(summons, SPELL_SPAWN_IN, false);
                 summons->AI()->Talk(SAY_ON_SPAWN_IN, player);
-                summons->m_Events.AddEvent(new DelayedWindstoneSummonEvent(summons, player->GetGUID()), summons->m_Events.CalculateTime(5200));
+                summons->m_Events.AddEventAtOffset(new DelayedWindstoneSummonEvent(summons, player->GetGUID()), 5200ms);
                 _creatureGuid = summons->GetGUID();
             }
         }
diff --git a/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_baltharus_the_warborn.cpp b/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_baltharus_the_warborn.cpp
index 56f0cc672..6d18a1602 100644
--- a/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_baltharus_the_warborn.cpp
+++ b/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_baltharus_the_warborn.cpp
@@ -152,7 +152,7 @@ public:
             if (action == ACTION_INTRO_BALTHARUS && !_introDone)
             {
                 _introDone = true;
-                me->m_Events.AddEvent(new DelayedTalk(me, SAY_BALTHARUS_INTRO), me->m_Events.CalculateTime(6000));
+                me->m_Events.AddEventAtOffset(new DelayedTalk(me, SAY_BALTHARUS_INTRO), 6s);
             }
             else if (action == ACTION_CLONE)
             {
@@ -204,7 +204,7 @@ public:
             summon->SetHealth(me->GetHealth());
             summon->CastSpell(summon, SPELL_SPAWN_EFFECT, true);
             summon->SetReactState(REACT_PASSIVE);
-            summon->m_Events.AddEvent(new RestoreFight(summon), summon->m_Events.CalculateTime(2000));
+            summon->m_Events.AddEventAtOffset(new RestoreFight(summon), 2s);
         }
 
         void UpdateAI(uint32 diff) override
diff --git a/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_halion.cpp b/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_halion.cpp
index d3107d148..b8c16d4bf 100644
--- a/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_halion.cpp
+++ b/src/server/scripts/Northrend/ChamberOfAspects/RubySanctum/boss_halion.cpp
@@ -1120,7 +1120,7 @@ class spell_halion_twilight_realm_aura : public AuraScript
         target->RemoveAurasDueToSpell(SPELL_FIERY_COMBUSTION, ObjectGuid::Empty, 0, AURA_REMOVE_BY_ENEMY_SPELL);
         if (!GetTarget()->IsPlayer())
             return;
-        GetTarget()->m_Events.AddEvent(new SendEncounterUnit(GetTarget()->ToPlayer()), GetTarget()->m_Events.CalculateTime(500));
+        GetTarget()->m_Events.AddEventAtOffset(new SendEncounterUnit(GetTarget()->ToPlayer()), 500ms);
     }
 
     void Register() override
@@ -1153,7 +1153,7 @@ class spell_halion_leave_twilight_realm_aura : public AuraScript
 
         if (!GetTarget()->IsPlayer())
             return;
-        GetTarget()->m_Events.AddEvent(new SendEncounterUnit(GetTarget()->ToPlayer()), GetTarget()->m_Events.CalculateTime(500));
+        GetTarget()->m_Events.AddEventAtOffset(new SendEncounterUnit(GetTarget()->ToPlayer()), 500ms);
     }
 
     void Register() override
diff --git a/src/server/scripts/Northrend/CrusadersColiseum/TrialOfTheCrusader/boss_anubarak_trial.cpp b/src/server/scripts/Northrend/CrusadersColiseum/TrialOfTheCrusader/boss_anubarak_trial.cpp
index 54b33f2b6..0e116a428 100644
--- a/src/server/scripts/Northrend/CrusadersColiseum/TrialOfTheCrusader/boss_anubarak_trial.cpp
+++ b/src/server/scripts/Northrend/CrusadersColiseum/TrialOfTheCrusader/boss_anubarak_trial.cpp
@@ -502,7 +502,7 @@ public:
         void JustDied(Unit*  /*killer*/) override
         {
             me->CastSpell(me, RAID_MODE(SPELL_TRAITOR_KING_10, SPELL_TRAITOR_KING_25, SPELL_TRAITOR_KING_10, SPELL_TRAITOR_KING_25), true);
-            me->m_Events.AddEvent(new HideNpcEvent(*me), me->m_Events.CalculateTime(5000));
+            me->m_Events.AddEventAtOffset(new HideNpcEvent(*me), 5s);
         }
 
         bool CanAIAttack(Unit const* target) const override
@@ -710,7 +710,7 @@ public:
 
         void JustDied(Unit*  /*killer*/) override
         {
-            me->m_Events.AddEvent(new HideNpcEvent(*me), me->m_Events.CalculateTime(5000));
+            me->m_Events.AddEventAtOffset(new HideNpcEvent(*me), 5s);
         }
 
         bool CanAIAttack(Unit const* target) const override
diff --git a/src/server/scripts/Northrend/FrozenHalls/HallsOfReflection/instance_halls_of_reflection.cpp b/src/server/scripts/Northrend/FrozenHalls/HallsOfReflection/instance_halls_of_reflection.cpp
index 5b1e99ab3..a22b42a61 100644
--- a/src/server/scripts/Northrend/FrozenHalls/HallsOfReflection/instance_halls_of_reflection.cpp
+++ b/src/server/scripts/Northrend/FrozenHalls/HallsOfReflection/instance_halls_of_reflection.cpp
@@ -38,7 +38,7 @@ public:
                 _owner.GetMotionMaster()->Clear();
                 _owner.SetVisible(true);
                 _owner.NearTeleportTo(5300.53f, 1987.80f, 707.70f, 3.89f);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, 2), _owner.m_Events.CalculateTime(1000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, 2), 1s);
                 break;
             case 2:
                 _owner.AI()->Talk(SAY_BATTERED_HILT_HALT);
@@ -52,12 +52,12 @@ public:
                 {
                     quel->AI()->Talk(EMOTE_QUEL_SPAWN);
                 }
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, 4), _owner.m_Events.CalculateTime(3500));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, 4), 3500ms);
                 break;
             case 4:
                 _owner.SetWalk(false);
                 _owner.GetMotionMaster()->MovePoint(0, 5337.53f, 1981.21f, 709.32f);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, 5), _owner.m_Events.CalculateTime(6000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, 5), 6s);
                 break;
             case 5:
                 _owner.SetFacingTo(2.82f);
@@ -66,7 +66,7 @@ public:
             case 6:
                 if (InstanceScript* instance = _owner.GetInstanceScript())
                     instance->SetData(DATA_BATTERED_HILT, 6);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, 7), _owner.m_Events.CalculateTime(2000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, 7), 2s);
                 break;
             case 7:
                 if (InstanceScript* instance = _owner.GetInstanceScript())
@@ -77,7 +77,7 @@ public:
                 {
                     quel->AI()->Talk(EMOTE_QUEL_PREPARE);
                 }
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, 8), _owner.m_Events.CalculateTime(4000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, 8), 4s);
                 break;
             case 8:
                 _owner.SetReactState(REACT_AGGRESSIVE);
@@ -87,23 +87,23 @@ public:
                 break;
             case 9:
                 _owner.AI()->Talk(SAY_BATTERED_HILT_OUTRO1);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, _eventId + 1), _owner.m_Events.CalculateTime(11000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, _eventId + 1), 11s);
                 break;
             case 10:
                 _owner.AI()->Talk(SAY_BATTERED_HILT_OUTRO2);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, _eventId + 1), _owner.m_Events.CalculateTime(7500));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, _eventId + 1), 7500ms);
                 break;
             case 11:
                 _owner.AI()->Talk(SAY_BATTERED_HILT_OUTRO3);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, _eventId + 1), _owner.m_Events.CalculateTime(8000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, _eventId + 1), 8s);
                 break;
             case 12:
                 _owner.AI()->Talk(SAY_BATTERED_HILT_OUTRO4);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, _eventId + 1), _owner.m_Events.CalculateTime(5000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, _eventId + 1), 5s);
                 break;
             case 13:
                 _owner.CastSpell((Unit*)nullptr, 73036, true);
-                _owner.m_Events.AddEvent(new UtherBatteredHiltEvent(_owner, _eventId + 1), _owner.m_Events.CalculateTime(3000));
+                _owner.m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(_owner, _eventId + 1), 3s);
                 break;
             case 14:
                 {
@@ -594,7 +594,7 @@ public:
                                 if (Creature* c = instance->GetCreature(NPC_AltarBunnyGUID))
                                     c->CastSpell(c, 70720, true);
                                 if (Creature* c = instance->GetCreature(NPC_UtherGUID))
-                                    c->m_Events.AddEvent(new UtherBatteredHiltEvent(*c, 1), c->m_Events.CalculateTime(3000));
+                                    c->m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(*c, 1), 3s);
                                 break;
                             case 3:
                                 if ((BatteredHiltStatus & BHSF_STARTED) == 0 || (BatteredHiltStatus & BHSF_THROWN))
@@ -602,7 +602,7 @@ public:
                                 BatteredHiltStatus |= BHSF_THROWN;
                                 if (Creature* c = instance->GetCreature(NPC_UtherGUID))
                                 {
-                                    c->m_Events.AddEvent(new UtherBatteredHiltEvent(*c, 3), c->m_Events.CalculateTime(5500));
+                                    c->m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(*c, 3), 5500ms);
                                 }
                                 break;
                             case 4:
@@ -614,7 +614,7 @@ public:
                                 break;
                             case 5:
                                 if (Creature* c = instance->GetCreature(NPC_UtherGUID))
-                                    c->m_Events.AddEvent(new UtherBatteredHiltEvent(*c, 6), c->m_Events.CalculateTime(3000));
+                                    c->m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(*c, 6), 3s);
                                 break;
                             case 6:
                                 if (Creature* c = instance->GetCreature(NPC_QuelDelarGUID))
@@ -726,7 +726,7 @@ public:
                     c->SetStandState(UNIT_STAND_STATE_STAND);
                     c->SetWalk(false);
                     c->GetMotionMaster()->MovePoint(0, 5313.92f, 1989.36f, 707.70f);
-                    c->m_Events.AddEvent(new UtherBatteredHiltEvent(*c, 9), c->m_Events.CalculateTime(7000));
+                    c->m_Events.AddEventAtOffset(new UtherBatteredHiltEvent(*c, 9), 7s);
                 }
         }
 
diff --git a/src/server/scripts/Northrend/FrozenHalls/PitOfSaron/pit_of_saron.cpp b/src/server/scripts/Northrend/FrozenHalls/PitOfSaron/pit_of_saron.cpp
index 805f21e46..b3174fb37 100644
--- a/src/server/scripts/Northrend/FrozenHalls/PitOfSaron/pit_of_saron.cpp
+++ b/src/server/scripts/Northrend/FrozenHalls/PitOfSaron/pit_of_saron.cpp
@@ -1383,7 +1383,7 @@ class spell_pos_slave_trigger_closest : public SpellScript
                         {
                             c->DespawnOrUnsummon(7s);
                             c->AI()->Talk(0, p);
-                            c->m_Events.AddEvent(new SlaveRunEvent(*c), c->m_Events.CalculateTime(3000));
+                            c->m_Events.AddEventAtOffset(new SlaveRunEvent(*c), 3s);
                         }
                     }
             }
diff --git a/src/server/scripts/Northrend/Gundrak/boss_drakkari_colossus.cpp b/src/server/scripts/Northrend/Gundrak/boss_drakkari_colossus.cpp
index c9caba5eb..7e1a25d7d 100644
--- a/src/server/scripts/Northrend/Gundrak/boss_drakkari_colossus.cpp
+++ b/src/server/scripts/Northrend/Gundrak/boss_drakkari_colossus.cpp
@@ -160,7 +160,7 @@ public:
             {
                 summon->SetRegeneratingHealth(false);
                 summon->SetReactState(REACT_PASSIVE);
-                summon->m_Events.AddEvent(new RestoreFight(summon), summon->m_Events.CalculateTime(3000));
+                summon->m_Events.AddEventAtOffset(new RestoreFight(summon), 3s);
                 if (!events.HasTimeUntilEvent(EVENT_COLOSSUS_HEALTH_2))
                 {
                     summon->SetHealth(summon->GetMaxHealth() / 2);
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/boss_blood_prince_council.cpp b/src/server/scripts/Northrend/IcecrownCitadel/boss_blood_prince_council.cpp
index 78baeb7eb..f34976029 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_blood_prince_council.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_blood_prince_council.cpp
@@ -375,7 +375,7 @@ public:
                     me->RemoveUnitFlag2(UNIT_FLAG2_FEIGN_DEATH);
                     me->SetReactState(REACT_AGGRESSIVE);
                     me->ForceValuesUpdateAtIndex(UNIT_NPC_FLAGS);   // was in sniff. don't ask why
-                    me->m_Events.AddEvent(new StandUpEvent(*me), me->m_Events.CalculateTime(1000));
+                    me->m_Events.AddEventAtOffset(new StandUpEvent(*me), 1s);
                     DoAction(ACTION_REMOVE_INVOCATION);
                     me->SetHealth(1);
                     break;
@@ -645,7 +645,7 @@ public:
                     me->RemoveUnitFlag2(UNIT_FLAG2_FEIGN_DEATH);
                     me->SetReactState(REACT_AGGRESSIVE);
                     me->ForceValuesUpdateAtIndex(UNIT_NPC_FLAGS);   // was in sniff. don't ask why
-                    me->m_Events.AddEvent(new StandUpEvent(*me), me->m_Events.CalculateTime(1000));
+                    me->m_Events.AddEventAtOffset(new StandUpEvent(*me), 1s);
                     DoAction(ACTION_REMOVE_INVOCATION);
                     me->SetHealth(1);
                     break;
@@ -889,7 +889,7 @@ public:
                     summon->CastSpell(summon, SPELL_KINETIC_BOMB, true, nullptr, nullptr, me->GetGUID());
                     break;
                 case NPC_SHOCK_VORTEX:
-                    summon->m_Events.AddEvent(new ShockVortexExplodeEvent(*summon), summon->m_Events.CalculateTime(4500));
+                    summon->m_Events.AddEventAtOffset(new ShockVortexExplodeEvent(*summon), 4500ms);
                     break;
                 default:
                     break;
@@ -939,7 +939,7 @@ public:
                     me->RemoveUnitFlag2(UNIT_FLAG2_FEIGN_DEATH);
                     me->SetReactState(REACT_AGGRESSIVE);
                     me->ForceValuesUpdateAtIndex(UNIT_NPC_FLAGS);   // was in sniff. don't ask why
-                    me->m_Events.AddEvent(new StandUpEvent(*me), me->m_Events.CalculateTime(1000));
+                    me->m_Events.AddEventAtOffset(new StandUpEvent(*me), 1s);
                     me->SetHealth(me->GetMaxHealth());
                     DoAction(ACTION_CAST_INVOCATION);
                     break;
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/boss_icecrown_gunship_battle.cpp b/src/server/scripts/Northrend/IcecrownCitadel/boss_icecrown_gunship_battle.cpp
index 3eda17921..b1239521b 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_icecrown_gunship_battle.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_icecrown_gunship_battle.cpp
@@ -373,7 +373,7 @@ class BattleExperienceEvent : public BasicEvent
 {
 public:
     static uint32 const ExperiencedSpells[5];
-    static uint32 const ExperiencedTimes[5];
+    static Milliseconds const ExperiencedTimes[5];
 
     BattleExperienceEvent(Creature* creature) : _creature(creature), _level(0) { }
 
@@ -388,7 +388,8 @@ public:
         _creature->CastSpell(_creature, ExperiencedSpells[_level], true);
         if (_level < (_creature->GetMap()->IsHeroic() ? 4 : 3))
         {
-            _creature->m_Events.AddEvent(this, timer + ExperiencedTimes[_level]);
+            Milliseconds nextExperienceEventTime = Milliseconds(timer) + ExperiencedTimes[_level];
+            _creature->m_Events.AddEventAtOffset(this, nextExperienceEventTime);
             return false;
         }
 
@@ -401,7 +402,7 @@ private:
 };
 
 uint32 const BattleExperienceEvent::ExperiencedSpells[5] = { 0, SPELL_EXPERIENCED, SPELL_VETERAN, SPELL_ELITE, SPELL_ADDS_BERSERK };
-uint32 const BattleExperienceEvent::ExperiencedTimes[5] = { 100000, 70000, 60000, 90000, 0 };
+Milliseconds const BattleExperienceEvent::ExperiencedTimes[5] = { 100s, 70s, 60s, 90s, 0ms };
 
 class PassengerController
 {
@@ -675,7 +676,7 @@ public:
             else
             {
                 uint32 teleportSpellId = _teamIdInInstance == TEAM_HORDE ? SPELL_TELEPORT_PLAYERS_ON_RESET_H : SPELL_TELEPORT_PLAYERS_ON_RESET_A;
-                me->m_Events.AddEvent(new ResetEncounterEvent(me, teleportSpellId, _instance->GetGuidData(DATA_ENEMY_GUNSHIP)), me->m_Events.CalculateTime(8000));
+                me->m_Events.AddEventAtOffset(new ResetEncounterEvent(me, teleportSpellId, _instance->GetGuidData(DATA_ENEMY_GUNSHIP)), 8s);
             }
         }
 
@@ -1544,7 +1545,7 @@ struct gunship_npc_AI : public ScriptedAI
         if (type == POINT_MOTION_TYPE && pointId == EVENT_CHARGE_PREPATH && Slot)
         {
             me->SetFacingTo(Slot->TargetPosition.GetOrientation());
-            me->m_Events.AddEvent(new BattleExperienceEvent(me), me->m_Events.CalculateTime(BattleExperienceEvent::ExperiencedTimes[0]));
+            me->m_Events.AddEventAtOffset(new BattleExperienceEvent(me), BattleExperienceEvent::ExperiencedTimes[0]);
             me->CastSpell(me, SPELL_BATTLE_EXPERIENCE, true);
             me->SetReactState(REACT_AGGRESSIVE);
         }
@@ -1579,7 +1580,7 @@ struct npc_gunship_boarding_addAI : public ScriptedAI
         {
             SetSlotInfo(data);
             me->SetReactState(REACT_PASSIVE);
-            me->m_Events.AddEvent(new DelayedMovementEvent(me, Slot->TargetPosition), me->m_Events.CalculateTime(3000 * (Index - SLOT_MARINE_1)));
+            me->m_Events.AddEventAtOffset(new DelayedMovementEvent(me, Slot->TargetPosition), Milliseconds(3000 * (Index - SLOT_MARINE_1)));
         }
     }
 
@@ -1608,7 +1609,7 @@ struct npc_gunship_boarding_addAI : public ScriptedAI
         if (type == POINT_MOTION_TYPE && pointId == EVENT_CHARGE_PREPATH && Slot)
         {
             me->SetFacingTo(Slot->TargetPosition.GetOrientation());
-            me->m_Events.AddEvent(new BattleExperienceEvent(me), me->m_Events.CalculateTime(BattleExperienceEvent::ExperiencedTimes[0]));
+            me->m_Events.AddEventAtOffset(new BattleExperienceEvent(me), BattleExperienceEvent::ExperiencedTimes[0]);
             me->CastSpell(me, SPELL_BATTLE_EXPERIENCE, true);
             me->SetReactState(REACT_AGGRESSIVE);
 
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/boss_lady_deathwhisper.cpp b/src/server/scripts/Northrend/IcecrownCitadel/boss_lady_deathwhisper.cpp
index 45dc33219..a29cc2cc6 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_lady_deathwhisper.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_lady_deathwhisper.cpp
@@ -522,7 +522,7 @@ public:
                     darnavan->GetMotionMaster()->MoveIdle();
                     darnavan->StopMoving();
                     darnavan->SetReactState(REACT_PASSIVE);
-                    darnavan->m_Events.AddEvent(new DaranavanMoveEvent(*darnavan), darnavan->m_Events.CalculateTime(10000));
+                    darnavan->m_Events.AddEventAtOffset(new DaranavanMoveEvent(*darnavan), 10s);
                     darnavan->AI()->Talk(SAY_DARNAVAN_RESCUED);
                     if (Player* owner = killer->GetCharmerOrOwnerPlayerOrPlayerItself())
                     {
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp b/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp
index 82ae8c8d3..2237cf87f 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp
@@ -384,7 +384,7 @@ public:
                 me->SetUnitFlag(UNIT_FLAG_NON_ATTACKABLE);
                 me->SetSpeed(MOVE_RUN, 4.28571f);
                 float moveTime = me->GetExactDist(&SindragosaFlyInPos) / (me->GetSpeed(MOVE_RUN) * 0.001f);
-                me->m_Events.AddEvent(new FrostwyrmLandEvent(*me, SindragosaLandPos), me->m_Events.CalculateTime(uint64(moveTime) + 250));
+                me->m_Events.AddEventAtOffset(new FrostwyrmLandEvent(*me, SindragosaLandPos), Milliseconds(uint32(moveTime) + 250));
                 me->GetMotionMaster()->MovePoint(POINT_FROSTWYRM_FLY_IN, SindragosaFlyInPos);
 
                 if (!instance->GetData(DATA_SINDRAGOSA_INTRO))
@@ -478,7 +478,7 @@ public:
         {
             summons.Summon(summon);
             if (summon->GetEntry() == NPC_FROST_BOMB)
-                summon->m_Events.AddEvent(new FrostBombExplosion(summon, me->GetGUID()), summon->m_Events.CalculateTime(5500));
+                summon->m_Events.AddEventAtOffset(new FrostBombExplosion(summon, me->GetGUID()), 5500ms);
         }
 
         void SummonedCreatureDespawn(Creature* summon) override
@@ -1079,7 +1079,7 @@ class spell_sindragosa_ice_tomb_trap_aura : public AuraScript
     void AfterApply(AuraEffect const* /*aurEff*/, AuraEffectHandleModes /*mode*/)
     {
         if (Unit* c = GetCaster())
-            GetTarget()->m_Events.AddEvent(new IceTombSummonEvent(GetTarget(), c->GetGUID()), GetTarget()->m_Events.CalculateTime(500));
+            GetTarget()->m_Events.AddEventAtOffset(new IceTombSummonEvent(GetTarget(), c->GetGUID()), 500ms);
     }
 
     void ExtraRemoveEffect(AuraEffect const* /*aurEff*/, AuraEffectHandleModes /*mode*/)
@@ -1245,7 +1245,7 @@ public:
                 me->setActive(true);
                 me->SetImmuneToPC(true);
                 float moveTime = me->GetExactDist(&SpinestalkerFlyPos) / (me->GetSpeed(MOVE_RUN) * 0.001f);
-                me->m_Events.AddEvent(new FrostwyrmLandEvent(*me, SpinestalkerLandPos), me->m_Events.CalculateTime(uint64(moveTime) + 250));
+                me->m_Events.AddEventAtOffset(new FrostwyrmLandEvent(*me, SpinestalkerLandPos), Milliseconds(uint32(moveTime) + 250));
                 me->SetDefaultMovementType(IDLE_MOTION_TYPE);
                 me->GetMotionMaster()->MoveIdle();
                 me->StopMoving();
@@ -1376,7 +1376,7 @@ public:
                 me->setActive(true);
                 me->SetImmuneToPC(true);
                 float moveTime = me->GetExactDist(&RimefangFlyPos) / (me->GetSpeed(MOVE_RUN) * 0.001f);
-                me->m_Events.AddEvent(new FrostwyrmLandEvent(*me, RimefangLandPos), me->m_Events.CalculateTime(uint64(moveTime) + 250));
+                me->m_Events.AddEventAtOffset(new FrostwyrmLandEvent(*me, RimefangLandPos), Milliseconds(uint32(moveTime) + 250));
                 me->SetDefaultMovementType(IDLE_MOTION_TYPE);
                 me->GetMotionMaster()->MoveIdle();
                 me->StopMoving();
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/boss_the_lich_king.cpp b/src/server/scripts/Northrend/IcecrownCitadel/boss_the_lich_king.cpp
index 0b04ad795..3aef1085b 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_the_lich_king.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_the_lich_king.cpp
@@ -552,7 +552,7 @@ public:
 
         if (--_counter)
         {
-            _owner->m_Events.AddEvent(this, _owner->m_Events.CalculateTime(3000));
+            _owner->m_Events.AddEventAtOffset(this, 3s);
             return false;
         }
 
@@ -830,8 +830,8 @@ public:
                     if (Creature* terenas = me->FindNearestCreature(NPC_TERENAS_MENETHIL_OUTRO, 50.0f))
                         terenas->DespawnOrUnsummon(1ms);
 
-                    me->m_Events.AddEvent(new LichKingDeathEvent(*me), me->m_Events.CalculateTime(2500)); // die after spinning anim is over, so death anim is visible
-                    me->m_Events.AddEvent(new LichKingMovieEvent(*me), me->m_Events.CalculateTime(11500));
+                    me->m_Events.AddEventAtOffset(new LichKingDeathEvent(*me), 2500ms); // die after spinning anim is over, so death anim is visible
+                    me->m_Events.AddEventAtOffset(new LichKingMovieEvent(*me), 11500ms);
                 }
 
                 if (!_bFordringMustFallYell && me->GetHealth() < 500000)
@@ -862,7 +862,7 @@ public:
                     summon->CastSpell(summon, SPELL_RISEN_WITCH_DOCTOR_SPAWN, true);
                     summon->SetReactState(REACT_PASSIVE);
                     summon->HandleEmoteCommand(EMOTE_ONESHOT_EMERGE);
-                    summon->m_Events.AddEvent(new StartMovementEvent(me, summon), summon->m_Events.CalculateTime(5000));
+                    summon->m_Events.AddEventAtOffset(new StartMovementEvent(me, summon), 5s);
                     break;
                 case NPC_RAGING_SPIRIT:
                     summon->SetHomePosition(CenterPosition);
@@ -872,7 +872,7 @@ public:
                         summon->SetReactState(REACT_PASSIVE);
                         summon->GetMotionMaster()->MoveRandom(10.0f);
                         if (_phase == PHASE_THREE)
-                            summon->m_Events.AddEvent(new VileSpiritActivateEvent(summon), summon->m_Events.CalculateTime(15000));
+                            summon->m_Events.AddEventAtOffset(new VileSpiritActivateEvent(summon), 15s);
                         break;
                     }
                 case NPC_STRANGULATE_VEHICLE:
@@ -1189,7 +1189,7 @@ public:
                             if (summon->GetEntry() == NPC_VILE_SPIRIT)
                             {
                                 summon->m_Events.KillAllEvents(true);
-                                summon->m_Events.AddEvent(new VileSpiritActivateEvent(summon), summon->m_Events.CalculateTime(55000));
+                                summon->m_Events.AddEventAtOffset(new VileSpiritActivateEvent(summon), 55s);
                                 summon->GetMotionMaster()->Clear(true);
                                 summon->StopMoving();
                                 summon->SetReactState(REACT_PASSIVE);
@@ -1213,7 +1213,7 @@ public:
                         {
                             spawner->CastSpell(spawner, SPELL_SUMMON_SPIRIT_BOMB_1, true);  // summons bombs randomly
                             spawner->CastSpell(spawner, SPELL_SUMMON_SPIRIT_BOMB_2, true);  // summons bombs on players
-                            spawner->m_Events.AddEvent(new TriggerWickedSpirit(spawner), spawner->m_Events.CalculateTime(3000));
+                            spawner->m_Events.AddEventAtOffset(new TriggerWickedSpirit(spawner), 3s);
                             terenas->SetImmuneToAll(true); // to avoid being healed by player trinket procs. terenas' health doesn't matter on heroic
                         }
                     }
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/boss_valithria_dreamwalker.cpp b/src/server/scripts/Northrend/IcecrownCitadel/boss_valithria_dreamwalker.cpp
index 4fa36acac..d04cfdafe 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_valithria_dreamwalker.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_valithria_dreamwalker.cpp
@@ -417,13 +417,13 @@ public:
         {
             if (summon->GetEntry() == NPC_DREAM_PORTAL_PRE_EFFECT)
             {
-                summon->m_Events.AddEvent(new DelayedCastEvent(summon, SPELL_SUMMON_DREAM_PORTAL, me->GetGUID(), 6s), summon->m_Events.CalculateTime(15000));
-                summon->m_Events.AddEvent(new AuraRemoveEvent(summon, SPELL_DREAM_PORTAL_VISUAL_PRE), summon->m_Events.CalculateTime(15000));
+                summon->m_Events.AddEventAtOffset(new DelayedCastEvent(summon, SPELL_SUMMON_DREAM_PORTAL, me->GetGUID(), 6s), 15s);
+                summon->m_Events.AddEventAtOffset(new AuraRemoveEvent(summon, SPELL_DREAM_PORTAL_VISUAL_PRE), 15s);
             }
             else if (summon->GetEntry() == NPC_NIGHTMARE_PORTAL_PRE_EFFECT)
             {
-                summon->m_Events.AddEvent(new DelayedCastEvent(summon, SPELL_SUMMON_NIGHTMARE_PORTAL, me->GetGUID(), 6s), summon->m_Events.CalculateTime(15000));
-                summon->m_Events.AddEvent(new AuraRemoveEvent(summon, SPELL_NIGHTMARE_PORTAL_VISUAL_PRE), summon->m_Events.CalculateTime(15000));
+                summon->m_Events.AddEventAtOffset(new DelayedCastEvent(summon, SPELL_SUMMON_NIGHTMARE_PORTAL, me->GetGUID(), 6s), 15s);
+                summon->m_Events.AddEventAtOffset(new AuraRemoveEvent(summon, SPELL_NIGHTMARE_PORTAL_VISUAL_PRE), 15s);
             }
         }
 
@@ -579,7 +579,7 @@ public:
         void DoAction(int32 action) override
         {
             if (action == ACTION_DEATH)
-                me->m_Events.AddEvent(new ValithriaDespawner(me), me->m_Events.CalculateTime(5000));
+                me->m_Events.AddEventAtOffset(new ValithriaDespawner(me), 5s);
             else if (action == ACTION_ENTER_COMBAT)
             {
                 if (!me->IsInCombat())
@@ -750,7 +750,7 @@ public:
         void JustSummoned(Creature* summon) override
         {
             if (summon->GetEntry() == NPC_COLUMN_OF_FROST)
-                summon->m_Events.AddEvent(new DelayedCastEvent(summon, SPELL_COLUMN_OF_FROST_DAMAGE, ObjectGuid::Empty, 8s), summon->m_Events.CalculateTime(2000));
+                summon->m_Events.AddEventAtOffset(new DelayedCastEvent(summon, SPELL_COLUMN_OF_FROST_DAMAGE, ObjectGuid::Empty, 8s), 2s);
             else if (summon->GetEntry() == NPC_MANA_VOID)
                 summon->DespawnOrUnsummon(36s);
         }
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/icecrown_citadel.cpp b/src/server/scripts/Northrend/IcecrownCitadel/icecrown_citadel.cpp
index 34069295d..5af60575c 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/icecrown_citadel.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/icecrown_citadel.cpp
@@ -1017,15 +1017,15 @@ public:
             if (Creature* crok = ObjectAccessor::GetCreature(*me, instance->GetGuidData(DATA_CROK_SCOURGEBANE))) // _isEventDone = true, setActive(false)
                 crok->AI()->DoAction(ACTION_RESET_EVENT);
 
-            uint64 delay = 6000;
+            Milliseconds delay = 6s;
             for (uint32 i = 0; i < 4; ++i)
                 if (Creature* crusader = ObjectAccessor::GetCreature(*me, instance->GetGuidData(DATA_CAPTAIN_ARNATH + i)))
                     if (crusader->IsAlive())
                     {
                         if (crusader->GetEntry() == crusader->GetCreatureData()->id1)
                         {
-                            crusader->m_Events.AddEvent(new CaptainSurviveTalk(*crusader), crusader->m_Events.CalculateTime(delay));
-                            delay += 6000;
+                            crusader->m_Events.AddEventAtOffset(new CaptainSurviveTalk(*crusader), delay);
+                            delay += 6s;
                         }
                         else
                             Unit::Kill(crusader, crusader);
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/instance_icecrown_citadel.cpp b/src/server/scripts/Northrend/IcecrownCitadel/instance_icecrown_citadel.cpp
index dbc3974ee..8298f5a75 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/instance_icecrown_citadel.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/instance_icecrown_citadel.cpp
@@ -513,7 +513,7 @@ public:
                             spellId = BLOOD_BEAM_VISUAL_LLEG;
                         else
                             spellId = BLOOD_BEAM_VISUAL_RLEG;
-                        creature->m_Events.AddEvent(new DelayedCastMincharEvent(creature, spellId), creature->m_Events.CalculateTime(1000));
+                        creature->m_Events.AddEventAtOffset(new DelayedCastMincharEvent(creature, spellId), 1s);
                     }
                     break;
                 case NPC_SKYBREAKER_DECKHAND:
@@ -608,7 +608,7 @@ public:
             std::string name2("Kor'kron ");
             if (!creature->GetTransport() && creature->GetPositionZ() <= 205.0f && creature->GetExactDist2d(-439.0f, 2210.0f) <= 150.0f && (creature->GetEntry() == 37544 || creature->GetEntry() == 37545 || creature->GetName().compare(0, name1.length(), name1) == 0 || creature->GetName().compare(0, name2.length(), name2) == 0))
                 if (!creature->GetLootRecipient())
-                    creature->m_Events.AddEvent(new RespawnEvent(*creature), creature->m_Events.CalculateTime(3000));
+                    creature->m_Events.AddEventAtOffset(new RespawnEvent(*creature), 3s);
 
             switch (creature->GetEntry())
             {
diff --git a/src/server/scripts/Northrend/Nexus/EyeOfEternity/boss_malygos.cpp b/src/server/scripts/Northrend/Nexus/EyeOfEternity/boss_malygos.cpp
index 2b49ebf29..a61e0089c 100644
--- a/src/server/scripts/Northrend/Nexus/EyeOfEternity/boss_malygos.cpp
+++ b/src/server/scripts/Northrend/Nexus/EyeOfEternity/boss_malygos.cpp
@@ -727,7 +727,7 @@ public:
                                     {
                                         c->SetFaction(pPlayer->GetFaction());
                                         //pPlayer->CastCustomSpell(60683, SPELLVALUE_BASE_POINT0, 1, c, true);
-                                        c->m_Events.AddEvent(new EoEDrakeEnterVehicleEvent(*c, pPlayer->GetGUID()), c->m_Events.CalculateTime(500));
+                                        c->m_Events.AddEventAtOffset(new EoEDrakeEnterVehicleEvent(*c, pPlayer->GetGUID()), 500ms);
                                         AttackStart(c);
                                     }
                                 }
diff --git a/src/server/scripts/Northrend/Nexus/EyeOfEternity/instance_eye_of_eternity.cpp b/src/server/scripts/Northrend/Nexus/EyeOfEternity/instance_eye_of_eternity.cpp
index 17de5127f..48e220df3 100644
--- a/src/server/scripts/Northrend/Nexus/EyeOfEternity/instance_eye_of_eternity.cpp
+++ b/src/server/scripts/Northrend/Nexus/EyeOfEternity/instance_eye_of_eternity.cpp
@@ -89,7 +89,7 @@ public:
                         c->SetCanFly(true);
                         c->SetFaction(pPlayer->GetFaction());
                         //pPlayer->CastCustomSpell(60683, SPELLVALUE_BASE_POINT0, 1, c, true);
-                        c->m_Events.AddEvent(new EoEDrakeEnterVehicleEvent(*c, pPlayer->GetGUID()), c->m_Events.CalculateTime(500));
+                        c->m_Events.AddEventAtOffset(new EoEDrakeEnterVehicleEvent(*c, pPlayer->GetGUID()), 500ms);
                     }
                 }
             }
diff --git a/src/server/scripts/Northrend/Nexus/Nexus/boss_anomalus.cpp b/src/server/scripts/Northrend/Nexus/Nexus/boss_anomalus.cpp
index 1be23abf8..717e7954f 100644
--- a/src/server/scripts/Northrend/Nexus/Nexus/boss_anomalus.cpp
+++ b/src/server/scripts/Northrend/Nexus/Nexus/boss_anomalus.cpp
@@ -171,7 +171,7 @@ struct boss_anomalus : public BossAI
 
             me->CastSpell(me, SPELL_CREATE_RIFT, false);
             me->CastSpell(me, SPELL_RIFT_SHIELD, true);
-            me->m_Events.AddEvent(new ChargeRifts(me), me->m_Events.CalculateTime(1000));
+            me->m_Events.AddEventAtOffset(new ChargeRifts(me), 1s);
             events.DelayEvents(46s);
             //As we just spawned an empowered spawn a normal one
             events.ScheduleEvent(EVENT_ANOMALUS_SPAWN_RIFT, IsHeroic() ? 15s : 25s);
diff --git a/src/server/scripts/Northrend/Ulduar/Ulduar/boss_algalon_the_observer.cpp b/src/server/scripts/Northrend/Ulduar/Ulduar/boss_algalon_the_observer.cpp
index 8a7db94e6..4d43d6f00 100644
--- a/src/server/scripts/Northrend/Ulduar/Ulduar/boss_algalon_the_observer.cpp
+++ b/src/server/scripts/Northrend/Ulduar/Ulduar/boss_algalon_the_observer.cpp
@@ -574,7 +574,7 @@ public:
                         summon->SetHomePosition(x, y, z, o);
                         summon->UpdatePosition(x, y, z, o, true);
                         summon->StopMovingOnCurrentPos();
-                        summon->m_Events.AddEvent(new CosmicSmashDamageEvent(summon), summon->m_Events.CalculateTime(4000));
+                        summon->m_Events.AddEventAtOffset(new CosmicSmashDamageEvent(summon), 4s);
                         break;
                     }
                 case NPC_UNLEASHED_DARK_MATTER:
diff --git a/src/server/scripts/Northrend/Ulduar/Ulduar/boss_assembly_of_iron.cpp b/src/server/scripts/Northrend/Ulduar/Ulduar/boss_assembly_of_iron.cpp
index 88b114633..1e6dec95f 100644
--- a/src/server/scripts/Northrend/Ulduar/Ulduar/boss_assembly_of_iron.cpp
+++ b/src/server/scripts/Northrend/Ulduar/Ulduar/boss_assembly_of_iron.cpp
@@ -418,7 +418,7 @@ public:
             if (pInstance)
                 pInstance->SetData(TYPE_ASSEMBLY, NOT_STARTED);
 
-            me->m_Events.AddEvent(new CastRunesEvent(*me), me->m_Events.CalculateTime(8000));
+            me->m_Events.AddEventAtOffset(new CastRunesEvent(*me), 8s);
         }
 
         void JustReachedHome() override
diff --git a/src/server/scripts/Northrend/Ulduar/Ulduar/boss_xt002.cpp b/src/server/scripts/Northrend/Ulduar/Ulduar/boss_xt002.cpp
index 1286139c3..570e7a266 100644
--- a/src/server/scripts/Northrend/Ulduar/Ulduar/boss_xt002.cpp
+++ b/src/server/scripts/Northrend/Ulduar/Ulduar/boss_xt002.cpp
@@ -769,12 +769,12 @@ public:
             // so that can't be the issue
             // See BoomEvent class
             // Schedule 1s delayed
-            me->m_Events.AddEvent(new BoomEvent(me), me->m_Events.CalculateTime(1 * IN_MILLISECONDS));
+            me->m_Events.AddEventAtOffset(new BoomEvent(me), 1s);
         }
 
         void JustDied(Unit* /*killer*/) override
         {
-            me->m_Events.AddEvent(new BoomEvent(me), me->m_Events.CalculateTime(1 * IN_MILLISECONDS));
+            me->m_Events.AddEventAtOffset(new BoomEvent(me), 1s);
         }
 
         void DamageTaken(Unit*, uint32& damage, DamageEffectType, SpellSchoolMask) override
diff --git a/src/server/scripts/Northrend/zone_dragonblight.cpp b/src/server/scripts/Northrend/zone_dragonblight.cpp
index b406df171..5710efa29 100644
--- a/src/server/scripts/Northrend/zone_dragonblight.cpp
+++ b/src/server/scripts/Northrend/zone_dragonblight.cpp
@@ -1439,7 +1439,7 @@ public:
         {
             me->SetDisplayId(me->GetNativeDisplayId());
             me->CastSpell(me, SPELL_SAC_EMERGE, true);
-            me->m_Events.AddEvent(new SACActivateEvent(me), me->m_Events.CalculateTime(4000));
+            me->m_Events.AddEventAtOffset(new SACActivateEvent(me), 4s);
         }
 
         void Deactivate()
@@ -1452,7 +1452,7 @@ public:
         void JustDied(Unit* /*killer*/) override
         {
             me->RemoveAurasDueToSpell(SPELL_SAC_GHOUL_AREA_AURA);
-            me->m_Events.AddEvent(new SACDeactivateEvent(me), me->m_Events.CalculateTime(4000));
+            me->m_Events.AddEventAtOffset(new SACDeactivateEvent(me), 4s);
         }
 
         void JustRespawned() override
diff --git a/src/server/scripts/Northrend/zone_storm_peaks.cpp b/src/server/scripts/Northrend/zone_storm_peaks.cpp
index b61003bca..559c8e823 100644
--- a/src/server/scripts/Northrend/zone_storm_peaks.cpp
+++ b/src/server/scripts/Northrend/zone_storm_peaks.cpp
@@ -975,7 +975,7 @@ public:
                 };
 
                 if (who->IsPlayer())
-                    who->m_Events.AddEvent(new DelayedTransportPositionOffsets(who), who->m_Events.CalculateTime(500));
+                    who->m_Events.AddEventAtOffset(new DelayedTransportPositionOffsets(who), 500ms);
 
                 return;
             }
diff --git a/src/server/scripts/Outland/BlackTemple/boss_illidari_council.cpp b/src/server/scripts/Outland/BlackTemple/boss_illidari_council.cpp
index c318e3871..880a39615 100644
--- a/src/server/scripts/Outland/BlackTemple/boss_illidari_council.cpp
+++ b/src/server/scripts/Outland/BlackTemple/boss_illidari_council.cpp
@@ -771,7 +771,7 @@ class spell_illidari_council_deadly_strike_aura : public AuraScript
         if (Unit* target = GetUnitOwner()->GetAI()->SelectTarget(SelectTargetMethod::Random, 0, 100.0f, true))
         {
             GetUnitOwner()->CastSpell(target, GetSpellInfo()->Effects[effect->GetEffIndex()].TriggerSpell, true);
-            GetUnitOwner()->m_Events.AddEvent(new VerasEnvenom(*GetUnitOwner(), target->GetGUID()), GetUnitOwner()->m_Events.CalculateTime(urand(1500, 3500)));
+            GetUnitOwner()->m_Events.AddEventAtOffset(new VerasEnvenom(*GetUnitOwner(), target->GetGUID()), randtime(1500ms, 3500ms));
         }
     }
 
diff --git a/src/server/scripts/Outland/BlackTemple/boss_reliquary_of_souls.cpp b/src/server/scripts/Outland/BlackTemple/boss_reliquary_of_souls.cpp
index 7b2d93442..9710a8382 100644
--- a/src/server/scripts/Outland/BlackTemple/boss_reliquary_of_souls.cpp
+++ b/src/server/scripts/Outland/BlackTemple/boss_reliquary_of_souls.cpp
@@ -284,7 +284,7 @@ public:
             if (type != POINT_MOTION_TYPE || id != POINT_GO_BACK)
                 return;
 
-            me->m_Events.AddEvent(new SuckBackEvent(*me, ACTION_ESSENCE_OF_SUFFERING), me->m_Events.CalculateTime(1500));
+            me->m_Events.AddEventAtOffset(new SuckBackEvent(*me, ACTION_ESSENCE_OF_SUFFERING), 1500ms);
             me->SetTarget();
             me->SetFacingTo(M_PI / 2.0f);
         }
@@ -392,7 +392,7 @@ public:
             if (type != POINT_MOTION_TYPE || id != POINT_GO_BACK)
                 return;
 
-            me->m_Events.AddEvent(new SuckBackEvent(*me, ACTION_ESSENCE_OF_DESIRE), me->m_Events.CalculateTime(1500));
+            me->m_Events.AddEventAtOffset(new SuckBackEvent(*me, ACTION_ESSENCE_OF_DESIRE), 1500ms);
             me->SetTarget();
             me->SetFacingTo(M_PI / 2.0f);
         }
diff --git a/src/server/scripts/Outland/TempestKeep/Eye/boss_alar.cpp b/src/server/scripts/Outland/TempestKeep/Eye/boss_alar.cpp
index 5d0ace11b..57b86cae3 100644
--- a/src/server/scripts/Outland/TempestKeep/Eye/boss_alar.cpp
+++ b/src/server/scripts/Outland/TempestKeep/Eye/boss_alar.cpp
@@ -452,10 +452,10 @@ class spell_alar_flame_quills : public AuraScript
 
         // 24 spells in total
         for (uint8 i = 0; i < 21; ++i)
-            GetUnitOwner()->m_Events.AddEvent(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_1 + i), GetUnitOwner()->m_Events.CalculateTime(i * 40));
-        GetUnitOwner()->m_Events.AddEvent(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_2 + 0), GetUnitOwner()->m_Events.CalculateTime(22 * 40));
-        GetUnitOwner()->m_Events.AddEvent(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_2 + 1), GetUnitOwner()->m_Events.CalculateTime(23 * 40));
-        GetUnitOwner()->m_Events.AddEvent(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_2 + 2), GetUnitOwner()->m_Events.CalculateTime(24 * 40));
+            GetUnitOwner()->m_Events.AddEventAtOffset(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_1 + i), Milliseconds(i * 40));
+        GetUnitOwner()->m_Events.AddEventAtOffset(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_2 + 0), Milliseconds(22 * 40));
+        GetUnitOwner()->m_Events.AddEventAtOffset(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_2 + 1), Milliseconds(23 * 40));
+        GetUnitOwner()->m_Events.AddEventAtOffset(new CastQuill(GetUnitOwner(), SPELL_QUILL_MISSILE_2 + 2), Milliseconds(24 * 40));
     }
 
     void Register() override
diff --git a/src/server/scripts/Outland/TempestKeep/Eye/boss_kaelthas.cpp b/src/server/scripts/Outland/TempestKeep/Eye/boss_kaelthas.cpp
index 0a1e1d064..871d014d9 100644
--- a/src/server/scripts/Outland/TempestKeep/Eye/boss_kaelthas.cpp
+++ b/src/server/scripts/Outland/TempestKeep/Eye/boss_kaelthas.cpp
@@ -1032,7 +1032,7 @@ public:
     bool Execute(uint64 /*execTime*/, uint32 /*diff*/) override
     {
         if (_owner->IsBeingTeleportedNear())
-            _owner->m_Events.AddEvent(new lapseTeleport(_owner), _owner->m_Events.CalculateTime(1));
+            _owner->m_Events.AddEventAtOffset(new lapseTeleport(_owner), 1ms);
         else if (!_owner->IsBeingTeleported())
         {
             _owner->CastSpell(_owner, SPELL_GRAVITY_LAPSE_KNOCKBACK, true);
@@ -1062,7 +1062,7 @@ class spell_kaelthas_gravity_lapse : public SpellScript
             if (Player* target = GetHitPlayer())
             {
                 GetCaster()->CastSpell(target, _currentSpellId++, true);
-                target->m_Events.AddEvent(new lapseTeleport(target), target->m_Events.CalculateTime(1));
+                target->m_Events.AddEventAtOffset(new lapseTeleport(target), 1ms);
             }
     }
 
diff --git a/src/server/scripts/Pet/pet_generic.cpp b/src/server/scripts/Pet/pet_generic.cpp
index 40c92b673..5b8fc12e1 100644
--- a/src/server/scripts/Pet/pet_generic.cpp
+++ b/src/server/scripts/Pet/pet_generic.cpp
@@ -193,7 +193,7 @@ struct npc_pet_gen_argent_pony_bridle : public ScriptedAI
                                 duration = cooldown;
                                 aura = SPELL_AURA_POSTMAN_S + i;
                                 _state = argentPonyService[TEAM_ALLIANCE][i];
-                                me->ToTempSummon()->UnSummon(duration);
+                                me->ToTempSummon()->UnSummon(Milliseconds(duration));
                                 break;
                             }
                         }
@@ -204,7 +204,7 @@ struct npc_pet_gen_argent_pony_bridle : public ScriptedAI
                                 duration = cooldown * IN_MILLISECONDS;
                                 aura = SPELL_AURA_BANK_G + i;
                                 _state = argentPonyService[TEAM_HORDE][i];
-                                me->ToTempSummon()->UnSummon(duration);
+                                me->ToTempSummon()->UnSummon(Milliseconds(duration));
                                 break;
                             }
                         }
diff --git a/src/server/scripts/Pet/pet_mage.cpp b/src/server/scripts/Pet/pet_mage.cpp
index 56a6c0ac5..9f3d40c3b 100644
--- a/src/server/scripts/Pet/pet_mage.cpp
+++ b/src/server/scripts/Pet/pet_mage.cpp
@@ -138,7 +138,7 @@ struct npc_pet_mage_mirror_image : CasterAI
                     newAura->SetDuration(visAura->GetDuration());
             }
 
-        me->m_Events.AddEvent(new DeathEvent(*me), me->m_Events.CalculateTime(29500));
+        me->m_Events.AddEventAtOffset(new DeathEvent(*me), 29500ms);
     }
 
     // Do not reload Creature templates on evade mode enter - prevent visual lost
diff --git a/src/server/scripts/Spells/spell_item.cpp b/src/server/scripts/Spells/spell_item.cpp
index e99d56478..25c46b9d5 100644
--- a/src/server/scripts/Spells/spell_item.cpp
+++ b/src/server/scripts/Spells/spell_item.cpp
@@ -1669,7 +1669,7 @@ public:
             _player->HandleEmoteCommand(RAND(EMOTE_ONESHOT_APPLAUD, EMOTE_ONESHOT_DANCESPECIAL, EMOTE_ONESHOT_LAUGH, EMOTE_ONESHOT_CHEER, EMOTE_ONESHOT_CHICKEN));
         }
 
-        _player->m_Events.AddEvent(this, RAND(_player->m_Events.CalculateTime(5000), _player->m_Events.CalculateTime(10000), _player->m_Events.CalculateTime(15000)));
+        _player->m_Events.AddEventAtOffset(this, RAND(5s, 10s, 15s));
 
         return false; // do not delete re-added event in EventProcessor::Update
     }
@@ -1690,7 +1690,7 @@ class spell_item_party_time : public AuraScript
             return;
         }
 
-        player->m_Events.AddEvent(new PartyTimeEmoteEvent(player), RAND(player->m_Events.CalculateTime(5000), player->m_Events.CalculateTime(10000), player->m_Events.CalculateTime(15000)));
+        player->m_Events.AddEventAtOffset(new PartyTimeEmoteEvent(player), RAND(5s, 10s, 15s));
     }
 
     void Register() override