diff --git a/src/server/game/Entities/Object/Object.cpp b/src/server/game/Entities/Object/Object.cpp
index 9c45722d4..b63514c40 100644
--- a/src/server/game/Entities/Object/Object.cpp
+++ b/src/server/game/Entities/Object/Object.cpp
@@ -1110,7 +1110,31 @@ bool WorldObject::_IsWithinDist(WorldObject const* obj, float dist2compare, bool
     return distsq < maxdist * maxdist;
 }
 
-bool WorldObject::IsWithinLOSInMap(const WorldObject* obj) const
+Position WorldObject::GetHitSpherePointFor(Position const& dest) const
+{
+    G3D::Vector3 vThis(GetPositionX(), GetPositionY(), GetPositionZ());
+    G3D::Vector3 vObj(dest.GetPositionX(), dest.GetPositionY(), dest.GetPositionZ());
+    G3D::Vector3 contactPoint = vThis + (vObj - vThis).directionOrZero() * std::min(dest.GetExactDist(this), GetObjectSize());
+
+    return Position(contactPoint.x, contactPoint.y, contactPoint.z, GetAngle(contactPoint.x, contactPoint.y));
+}
+
+bool WorldObject::IsWithinLOS(float ox, float oy, float oz, LineOfSightChecks checks) const
+{ 
+    if (IsInWorld())
+    {
+        float x, y, z;
+        if (GetTypeId() == TYPEID_PLAYER)
+            GetPosition(x, y, z);
+        else
+            GetHitSpherePointFor({ ox, oy, oz }, x, y, z);
+
+        return GetMap()->isInLineOfSight(x, y, z + 2.0f, ox, oy, oz + 2.0f, GetPhaseMask(), checks);
+    }
+    return true;
+}
+
+bool WorldObject::IsWithinLOSInMap(const WorldObject* obj, LineOfSightChecks checks) const
 {
     if (!IsInMap(obj))
         return false;
@@ -1121,36 +1145,7 @@ bool WorldObject::IsWithinLOSInMap(const WorldObject* obj) const
     else
         obj->GetHitSpherePointFor(GetPosition(), x, y, z);
 
-    return IsWithinLOS(x, y, z);
-}
-
-bool WorldObject::IsWithinLOS(float ox, float oy, float oz) const
-{ 
-    /*float x, y, z;
-    GetPosition(x, y, z);
-    VMAP::IVMapManager* vMapManager = VMAP::VMapFactory::createOrGetVMapManager();
-    return vMapManager->isInLineOfSight(GetMapId(), x, y, z+2.0f, ox, oy, oz+2.0f);*/
-    if (IsInWorld())
-    {
-        float x, y, z;
-        if (GetTypeId() == TYPEID_PLAYER)
-            GetPosition(x, y, z);
-        else
-            GetHitSpherePointFor({ ox, oy, oz }, x, y, z);
-
-        return GetMap()->isInLineOfSight(x, y, z + 2.0f, ox, oy, oz + 2.0f, GetPhaseMask());
-    }
-
-    return true;
-}
-
-Position WorldObject::GetHitSpherePointFor(Position const& dest) const
-{
-    G3D::Vector3 vThis(GetPositionX(), GetPositionY(), GetPositionZ());
-    G3D::Vector3 vObj(dest.GetPositionX(), dest.GetPositionY(), dest.GetPositionZ());
-    G3D::Vector3 contactPoint = vThis + (vObj - vThis).directionOrZero() * std::min(dest.GetExactDist(this), GetObjectSize());
-
-    return Position(contactPoint.x, contactPoint.y, contactPoint.z, GetAngle(contactPoint.x, contactPoint.y));
+    return IsWithinLOS(x, y, z, checks);
 }
 
 void WorldObject::GetHitSpherePointFor(Position const& dest, float& x, float& y, float& z) const
diff --git a/src/server/game/Entities/Object/Object.h b/src/server/game/Entities/Object/Object.h
index 0d779cd75..7530d2630 100644
--- a/src/server/game/Entities/Object/Object.h
+++ b/src/server/game/Entities/Object/Object.h
@@ -865,8 +865,8 @@ class WorldObject : public Object, public WorldLocation
         {
             return obj && IsInMap(obj) && InSamePhase(obj) && _IsWithinDist(obj, dist2compare, is3D);
         }
-        bool IsWithinLOS(float x, float y, float z) const;
-        bool IsWithinLOSInMap(const WorldObject* obj) const;
+        bool IsWithinLOS(float x, float y, float z, LineOfSightChecks checks = LINEOFSIGHT_ALL_CHECKS) const;
+        bool IsWithinLOSInMap(WorldObject const* obj, LineOfSightChecks checks = LINEOFSIGHT_ALL_CHECKS) const;
         Position GetHitSpherePointFor(Position const& dest) const;
         void GetHitSpherePointFor(Position const& dest, float& x, float& y, float& z) const;
         bool GetDistanceOrder(WorldObject const* obj1, WorldObject const* obj2, bool is3D = true) const;
diff --git a/src/server/game/Maps/Map.cpp b/src/server/game/Maps/Map.cpp
index efde5585d..107d978f5 100644
--- a/src/server/game/Maps/Map.cpp
+++ b/src/server/game/Maps/Map.cpp
@@ -2164,10 +2164,15 @@ float Map::GetWaterLevel(float x, float y) const
         return 0;
 }
 
-bool Map::isInLineOfSight(float x1, float y1, float z1, float x2, float y2, float z2, uint32 phasemask) const
-{ 
-    return VMAP::VMapFactory::createOrGetVMapManager()->isInLineOfSight(GetId(), x1, y1, z1, x2, y2, z2)
-        && _dynamicTree.isInLineOfSight(x1, y1, z1, x2, y2, z2, phasemask);
+bool Map::isInLineOfSight(float x1, float y1, float z1, float x2, float y2, float z2, uint32 phasemask, LineOfSightChecks checks) const
+{
+    if ((checks & LINEOFSIGHT_CHECK_VMAP) && !VMAP::VMapFactory::createOrGetVMapManager()->isInLineOfSight(GetId(), x1, y1, z1, x2, y2, z2))
+        return false;
+    
+    if (sWorld->getBoolConfig(CONFIG_CHECK_GOBJECT_LOS) && (checks & LINEOFSIGHT_CHECK_GOBJECT)
+      && !_dynamicTree.isInLineOfSight(x1, y1, z1, x2, y2, z2, phasemask))
+        return false;
+    return true;
 }
 
 bool Map::getObjectHitPos(uint32 phasemask, float x1, float y1, float z1, float x2, float y2, float z2, float& rx, float& ry, float& rz, float modifyDist)
diff --git a/src/server/game/Maps/Map.h b/src/server/game/Maps/Map.h
index 44c5c2ccf..a8cd46205 100644
--- a/src/server/game/Maps/Map.h
+++ b/src/server/game/Maps/Map.h
@@ -142,6 +142,14 @@ struct LiquidData
     float  depth_level;
 };
 
+enum LineOfSightChecks
+{
+    LINEOFSIGHT_CHECK_VMAP      = 0x1, // check static floor layout data
+    LINEOFSIGHT_CHECK_GOBJECT   = 0x2, // check dynamic game object data
+
+    LINEOFSIGHT_ALL_CHECKS      = (LINEOFSIGHT_CHECK_VMAP | LINEOFSIGHT_CHECK_GOBJECT)
+};
+
 class GridMap
 {
     uint32  _flags;
@@ -448,7 +456,7 @@ class Map : public GridRefManager<NGridType>
 
         float GetWaterOrGroundLevel(float x, float y, float z, float* ground = NULL, bool swim = false, float maxSearchDist = 50.0f) const;
         float GetHeight(uint32 phasemask, float x, float y, float z, bool vmap = true, float maxSearchDist = DEFAULT_HEIGHT_SEARCH) const;
-        bool isInLineOfSight(float x1, float y1, float z1, float x2, float y2, float z2, uint32 phasemask) const;
+        bool isInLineOfSight(float x1, float y1, float z1, float x2, float y2, float z2, uint32 phasemask, LineOfSightChecks checks) const;
         void Balance() { _dynamicTree.balance(); }
         void RemoveGameObjectModel(const GameObjectModel& model) { _dynamicTree.remove(model); }
         void InsertGameObjectModel(const GameObjectModel& model) { _dynamicTree.insert(model); }
diff --git a/src/server/game/Movement/MovementGenerators/RandomMovementGenerator.cpp b/src/server/game/Movement/MovementGenerators/RandomMovementGenerator.cpp
index f3b09f40a..b1a1868d2 100644
--- a/src/server/game/Movement/MovementGenerators/RandomMovementGenerator.cpp
+++ b/src/server/game/Movement/MovementGenerators/RandomMovementGenerator.cpp
@@ -145,7 +145,7 @@ void RandomMovementGenerator<Creature>::_setRandomLocation(Creature* creature)
                         return;
                     }
 
-                    if (!map->isInLineOfSight((*itr).x, (*itr).y, (*itr).z+2.f, (*itrNext).x, (*itrNext).y, (*itrNext).z+2.f, creature->GetPhaseMask()))
+                    if (!map->isInLineOfSight((*itr).x, (*itr).y, (*itr).z+2.f, (*itrNext).x, (*itrNext).y, (*itrNext).z+2.f, creature->GetPhaseMask(), LINEOFSIGHT_ALL_CHECKS))
                     {
                         _validPointsVector[_currentPoint].erase(randomIter);
                         _preComputedPaths.erase(pathIdx);
diff --git a/src/server/game/Spells/Spell.cpp b/src/server/game/Spells/Spell.cpp
index acbbc8c04..cd286f3fb 100644
--- a/src/server/game/Spells/Spell.cpp
+++ b/src/server/game/Spells/Spell.cpp
@@ -2191,7 +2191,7 @@ void Spell::SearchChainTargets(std::list<WorldObject*>& targets, uint32 chainTar
                 if (Unit* unit = (*itr)->ToUnit())
                 {
                     uint32 deficit = unit->GetMaxHealth() - unit->GetHealth();
-                    if ((deficit > maxHPDeficit || foundItr == tempTargets.end()) && target->IsWithinDist(unit, jumpRadius) && target->IsWithinLOSInMap(unit))
+                    if ((deficit > maxHPDeficit || foundItr == tempTargets.end()) && target->IsWithinDist(unit, jumpRadius) && target->IsWithinLOSInMap(unit, LINEOFSIGHT_ALL_CHECKS))
                     {
                         foundItr = itr;
                         maxHPDeficit = deficit;
@@ -2206,10 +2206,10 @@ void Spell::SearchChainTargets(std::list<WorldObject*>& targets, uint32 chainTar
             {
                 if (foundItr == tempTargets.end())
                 {
-                    if ((!isBouncingFar || target->IsWithinDist(*itr, jumpRadius)) && target->IsWithinLOSInMap(*itr))
+                    if ((!isBouncingFar || target->IsWithinDist(*itr, jumpRadius)) && target->IsWithinLOSInMap(*itr, LINEOFSIGHT_ALL_CHECKS))
                         foundItr = itr;
                 }
-                else if (target->GetDistanceOrder(*itr, *foundItr) && target->IsWithinLOSInMap(*itr))
+                else if (target->GetDistanceOrder(*itr, *foundItr) && target->IsWithinLOSInMap(*itr, LINEOFSIGHT_ALL_CHECKS))
                     foundItr = itr;
             }
         }
@@ -5518,7 +5518,7 @@ SpellCastResult Spell::CheckCast(bool strict)
                 return SPELL_FAILED_NOT_INFRONT;
 
             if (m_caster->GetEntry() != WORLD_TRIGGER) // Ignore LOS for gameobjects casts (wrongly casted by a trigger)
-                if ((!m_caster->IsTotem() || !m_spellInfo->IsPositive()) && !m_spellInfo->HasAttribute(SPELL_ATTR2_CAN_TARGET_NOT_IN_LOS) && !m_spellInfo->HasAttribute(SPELL_ATTR5_SKIP_CHECKCAST_LOS_CHECK) && !m_caster->IsWithinLOSInMap(target) && !(m_spellFlags & SPELL_FLAG_REDIRECTED))
+                if ((!m_caster->IsTotem() || !m_spellInfo->IsPositive()) && !m_spellInfo->HasAttribute(SPELL_ATTR2_CAN_TARGET_NOT_IN_LOS) && !m_spellInfo->HasAttribute(SPELL_ATTR5_SKIP_CHECKCAST_LOS_CHECK) && !m_caster->IsWithinLOSInMap(target, LINEOFSIGHT_ALL_CHECKS) && !(m_spellFlags & SPELL_FLAG_REDIRECTED))
                     return SPELL_FAILED_LINE_OF_SIGHT;
         }
     }
@@ -5529,7 +5529,7 @@ SpellCastResult Spell::CheckCast(bool strict)
         float x, y, z;
         m_targets.GetDstPos()->GetPosition(x, y, z);
 
-        if ((!m_caster->IsTotem() || !m_spellInfo->IsPositive()) && !m_spellInfo->HasAttribute(SPELL_ATTR2_CAN_TARGET_NOT_IN_LOS) && !m_spellInfo->HasAttribute(SPELL_ATTR5_SKIP_CHECKCAST_LOS_CHECK) && !m_caster->IsWithinLOS(x, y, z))
+        if ((!m_caster->IsTotem() || !m_spellInfo->IsPositive()) && !m_spellInfo->HasAttribute(SPELL_ATTR2_CAN_TARGET_NOT_IN_LOS) && !m_spellInfo->HasAttribute(SPELL_ATTR5_SKIP_CHECKCAST_LOS_CHECK) && !m_caster->IsWithinLOS(x, y, z, LINEOFSIGHT_ALL_CHECKS))
             return SPELL_FAILED_LINE_OF_SIGHT;
     }
 
@@ -5708,7 +5708,7 @@ SpellCastResult Spell::CheckCast(bool strict)
                     if (!target || !pet || pet->isDead() || target->isDead())
                         return SPELL_FAILED_BAD_TARGETS;
                     
-                    if (!pet->IsWithinLOSInMap(target))
+                    if (!pet->IsWithinLOSInMap(target, LINEOFSIGHT_ALL_CHECKS))
                         return SPELL_FAILED_LINE_OF_SIGHT;
                 }
                 break;
@@ -7418,7 +7418,7 @@ bool Spell::CheckEffectTarget(Unit const* target, uint32 eff) const
             z = m_targets.GetDstPos()->GetPositionZ();
         }
 
-        if ((!m_caster->IsTotem() || !m_spellInfo->IsPositive()) && !target->IsWithinLOS(x, y, z))
+        if ((!m_caster->IsTotem() || !m_spellInfo->IsPositive()) && !target->IsWithinLOS(x, y, z, LINEOFSIGHT_ALL_CHECKS))
             return false;
 
         return true;
@@ -7430,7 +7430,7 @@ bool Spell::CheckEffectTarget(Unit const* target, uint32 eff) const
     {
         case SPELL_EFFECT_RESURRECT_NEW:
             // player far away, maybe his corpse near?
-            if (target != m_caster && !target->IsWithinLOSInMap(m_caster))
+            if (target != m_caster && !target->IsWithinLOSInMap(m_caster, LINEOFSIGHT_ALL_CHECKS))
             {
                 if (!m_targets.GetCorpseTargetGUID())
                     return false;
@@ -7442,7 +7442,7 @@ bool Spell::CheckEffectTarget(Unit const* target, uint32 eff) const
                 if (target->GetGUID() != corpse->GetOwnerGUID())
                     return false;
 
-                if (!corpse->IsWithinLOSInMap(m_caster) && !(m_spellFlags & SPELL_FLAG_REDIRECTED))
+                if (!corpse->IsWithinLOSInMap(m_caster, LINEOFSIGHT_ALL_CHECKS) && !(m_spellFlags & SPELL_FLAG_REDIRECTED))
                     return false;
             }
             break;
@@ -7450,7 +7450,7 @@ bool Spell::CheckEffectTarget(Unit const* target, uint32 eff) const
             {
                 if (!m_targets.GetCorpseTargetGUID())
                 {
-                    if (target->IsWithinLOSInMap(m_caster) && target->HasFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_SKINNABLE))
+                    if (target->IsWithinLOSInMap(m_caster, LINEOFSIGHT_ALL_CHECKS) && target->HasFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_SKINNABLE))
                         return true;
 
                     return false;
@@ -7466,7 +7466,7 @@ bool Spell::CheckEffectTarget(Unit const* target, uint32 eff) const
                 if (!corpse->HasFlag(CORPSE_FIELD_FLAGS, CORPSE_FLAG_LOOTABLE))
                     return false;
 
-                if (!corpse->IsWithinLOSInMap(m_caster))
+                if (!corpse->IsWithinLOSInMap(m_caster, LINEOFSIGHT_ALL_CHECKS))
                     return false;
             }
             break;
@@ -7503,7 +7503,7 @@ bool Spell::CheckEffectTarget(Unit const* target, uint32 eff) const
                     z = m_targets.GetDstPos()->GetPositionZ();
                 }
 
-                if (!target->IsInMap(caster) || !target->IsWithinLOS(x, y, z))
+                if (!target->IsInMap(caster) || !target->IsWithinLOS(x, y, z, LINEOFSIGHT_ALL_CHECKS))
                     return false;
             }
             break;
diff --git a/src/server/game/World/World.cpp b/src/server/game/World/World.cpp
index ede71d2eb..d1a82ee70 100644
--- a/src/server/game/World/World.cpp
+++ b/src/server/game/World/World.cpp
@@ -1297,7 +1297,10 @@ void World::LoadConfigSettings(bool reload)
     m_bool_configs[CONFIG_ENABLE_CONTINENT_TRANSPORT_PRELOADING] = sConfigMgr->GetBoolDefault("IsPreloadedContinentTransport.Enabled", false);
 
     m_bool_configs[CONFIG_IP_BASED_ACTION_LOGGING] = sConfigMgr->GetBoolDefault("Allow.IP.Based.Action.Logging", false);
-  
+
+    // Whether to use LoS from game objects
+    m_bool_configs[CONFIG_CHECK_GOBJECT_LOS] = sConfigMgr->GetBoolDefault("CheckGameObjectLoS", true);
+
     m_bool_configs[CONFIG_CALCULATE_CREATURE_ZONE_AREA_DATA] = sConfigMgr->GetBoolDefault("Calculate.Creature.Zone.Area.Data", false);
     m_bool_configs[CONFIG_CALCULATE_GAMEOBJECT_ZONE_AREA_DATA] = sConfigMgr->GetBoolDefault("Calculate.Gameoject.Zone.Area.Data", false);
 
diff --git a/src/server/game/World/World.h b/src/server/game/World/World.h
index c4ba65335..a6d37e25f 100644
--- a/src/server/game/World/World.h
+++ b/src/server/game/World/World.h
@@ -165,6 +165,7 @@ enum WorldBoolConfigs
     CONFIG_IP_BASED_ACTION_LOGGING,
     CONFIG_CALCULATE_CREATURE_ZONE_AREA_DATA,
     CONFIG_CALCULATE_GAMEOBJECT_ZONE_AREA_DATA,
+    CONFIG_CHECK_GOBJECT_LOS,
     BOOL_CONFIG_VALUE_COUNT
 };
 
diff --git a/src/server/scripts/Commands/cs_debug.cpp b/src/server/scripts/Commands/cs_debug.cpp
index 2f1a65593..bac6d9f8d 100644
--- a/src/server/scripts/Commands/cs_debug.cpp
+++ b/src/server/scripts/Commands/cs_debug.cpp
@@ -1047,8 +1047,15 @@ public:
     static bool HandleDebugLoSCommand(ChatHandler* handler, char const* /*args*/)
     {
         if (Unit* unit = handler->getSelectedUnit())
-            handler->PSendSysMessage("Unit %s (GuidLow: %u) is %sin LoS", unit->GetName().c_str(), unit->GetGUIDLow(), handler->GetSession()->GetPlayer()->IsWithinLOSInMap(unit) ? "" : "not ");
-        return true;
+        {
+            Player* player = handler->GetSession()->GetPlayer();
+            handler->PSendSysMessage("Checking LoS %s -> %s:", player->GetName().c_str(), unit->GetName().c_str());
+            handler->PSendSysMessage("    VMAP LoS: %s", player->IsWithinLOSInMap(unit, LINEOFSIGHT_CHECK_VMAP) ? "clear" : "obstructed");
+            handler->PSendSysMessage("    GObj LoS: %s", player->IsWithinLOSInMap(unit, LINEOFSIGHT_CHECK_GOBJECT) ? "clear" : "obstructed");
+            handler->PSendSysMessage("%s is %sin line of sight of %s.", unit->GetName().c_str(), (player->IsWithinLOSInMap(unit) ? "" : "not "), player->GetName().c_str());
+            return true;
+        }
+        return false;
     }
 
     static bool HandleDebugSetAuraStateCommand(ChatHandler* handler, char const* args)
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 87a423a3b..f95c81087 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_blood_prince_council.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_blood_prince_council.cpp
@@ -1696,7 +1696,7 @@ class spell_blood_council_summon_shadow_resonance : public SpellScriptLoader
                     {
                         float destX = summoner->GetPositionX()+cos(angle + a*M_PI)*i*10.0f;
                         float destY = summoner->GetPositionY()+sin(angle + a*M_PI)*i*10.0f;
-                        if (summoner->GetMap()->isInLineOfSight(summoner->GetPositionX(), summoner->GetPositionY(), summoner->GetPositionZ()+10.0f, destX, destY, summoner->GetPositionZ()+10.0f, summoner->GetPhaseMask()) && destX > 4585.0f && destY > 2716.0f && destY < 2822.0f)
+                        if (summoner->GetMap()->isInLineOfSight(summoner->GetPositionX(), summoner->GetPositionY(), summoner->GetPositionZ()+10.0f, destX, destY, summoner->GetPositionZ()+10.0f, summoner->GetPhaseMask(), LINEOFSIGHT_ALL_CHECKS) && destX > 4585.0f && destY > 2716.0f && destY < 2822.0f)
                         {
                             float destZ = summoner->GetMap()->GetHeight(summoner->GetPhaseMask(), destX, destY, summoner->GetPositionZ()+10.0f);
                             if (fabs(destZ-summoner->GetPositionZ()) < 10.0f) // valid z found
diff --git a/src/server/scripts/Northrend/Ulduar/Ulduar/ulduar.cpp b/src/server/scripts/Northrend/Ulduar/Ulduar/ulduar.cpp
index 32618e6e2..ad4d6b30c 100644
--- a/src/server/scripts/Northrend/Ulduar/Ulduar/ulduar.cpp
+++ b/src/server/scripts/Northrend/Ulduar/Ulduar/ulduar.cpp
@@ -202,7 +202,7 @@ public:
         void MoveInLineOfSight(Unit* who)
         {
             if (!activated && who->GetTypeId() == TYPEID_PLAYER)
-                if (me->GetExactDist2d(who) <= 25.0f && me->GetMap()->isInLineOfSight(me->GetPositionX(), me->GetPositionY(), me->GetPositionZ()+5.0f, who->GetPositionX(), who->GetPositionY(), who->GetPositionZ()+5.0f, 2))
+                if (me->GetExactDist2d(who) <= 25.0f && me->GetMap()->isInLineOfSight(me->GetPositionX(), me->GetPositionY(), me->GetPositionZ()+5.0f, who->GetPositionX(), who->GetPositionY(), who->GetPositionZ()+5.0f, 2, LINEOFSIGHT_ALL_CHECKS))
                 {
                     activated = true;
                     me->RemoveAura(64615);
diff --git a/src/server/worldserver/worldserver.conf.dist b/src/server/worldserver/worldserver.conf.dist
index 3f6c5164e..81815f97f 100644
--- a/src/server/worldserver/worldserver.conf.dist
+++ b/src/server/worldserver/worldserver.conf.dist
@@ -318,6 +318,15 @@ vmap.enableIndoorCheck = 1
 
 DetectPosCollision = 1
 
+#
+#    CheckGameObjectLoS
+#        Description: Include dynamic game objects (doors, chests etc.) in line of sight checks.
+#                     This increases CPU usage somewhat.
+#        Default:     1 - (Enabled)
+#                     0 - (Disabled, may break some boss encounters)
+
+CheckGameObjectLoS = 1
+
 #
 #    TargetPosRecalculateRange
 #        Description: Max distance from movement target point (+moving unit size) and targeted