Custom boss - randomly leaves combat

[singoe]

I made this script for a boss on my server, but after 6-7 secconds he leaves combat for no reason. I took away the script and he works fine. Does anyone see the problem with the script?

function Archedonus_OnCombat(Unit, Event)
	Unit:SendChatMessage(14, 0, "You dare challenge me?! Ha! I am the creator! I will make all of you my puppets!")
		Unit:RegisterEvent("HeroicStrike", 8000, 0)
		Unit:RegisterEvent("DetonateMana", 10000, 0)
		Unit:RegisterEvent("Polymorph", 8000, 0)
		Unit:RegisterEvent("Meteor", 16000, 0)	
end

function HeroicStrike(Unit, Event)
	Unit:FullCastSpellOnTarget(41975, Unit:GetMainTank(1))
end

function DetonateMana(Unit, Event)
	Unit:FullCastSpellOnTarget(27819, Unit:GetRandomPlayer(4))
end

function Polymorph(Unit, Event)
	Unit:FullCastSpellOnTarget(27819, Unit:GetRandomPlayer(7))
end

function Meteor(Unit, Event)
	Unit:FullCastSpellOnTarget(45150, Unit:GetRandomPlayer(0))
end

function Archedonus_OnLeaveCombat(Unit, Event)
	Unit:SendChatMessage(14, 0, "Ill go back to my teamaking.?!")
		Unit:RemoveEvents()
end

function Archedonus_OnKilledTarget(Unit, Event)
	Unit:SendChatMessage(14, 0, "Ha! Pitiful soul, you only add to my power!")
		Unit:CastSpell(40318)
end

function Archedonus_OnDied(Unit, Event)
	Unit:SendChatMessage(14, 0, "How?! How could this have happened?!")
		Unit:RemoveEvents()
end

RegisterUnitEvent(700001,1,"Archedonus_OnCombat")
RegisterUnitEvent(700001,2,"Archedonus_OnLeaveCombat")
RegisterUnitEvent(700001,3,"Archedonus_OnKilledTarget")
RegisterUnitEvent(700001,4,"Archedonus_OnDied")

[Pedregon]

I't could be a spell that's causing this, where it's trying to cast a spell that doesn't work so it resets itselfs, try checking which spell it's using before it leaves combat, remove it and try it again.