diff --git a/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_muru.cpp b/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_muru.cpp
index 430ff20ee..7638efe9a 100644
--- a/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_muru.cpp
+++ b/src/server/scripts/EasternKingdoms/SunwellPlateau/boss_muru.cpp
@@ -342,7 +342,7 @@ class spell_entropius_negative_energy_periodic : public AuraScript
     void PeriodicTick(AuraEffect const* aurEff)
     {
         PreventDefaultAction();
-        uint32 targetCount = aurEff->GetTickNumber() > 12 ? 1 : aurEff->GetTickNumber() / 12;
+        uint32 targetCount = (aurEff->GetTickNumber() + 11) / 12;
         GetTarget()->CastCustomSpell(aurEff->GetSpellInfo()->Effects[EFFECT_0].TriggerSpell, SPELLVALUE_MAX_TARGETS, targetCount);
     }