EmuDevs: Eluna - Creature AI RegisterEvent

local npcId = 90000

function OnReset(event, creature)
    creature:AddAura(30000, creature)
end

function OnEnterCombat(event, creature, target)
   creature:CastSpell(target, 20000, true)
   creature:RegisterEvent(OnScaleChange, 1000, 1)
   creature:RegisterEvent(OnCheckHealth, 1000, 0)
end

function OnScaleChange(event, delay, pCall, creature)
    creature:RemoveEventById(event)
    creature:SetScale(2)
end

function OnCheckHealth(event, delay, pCall, creature)
    if (creature:GetHealthPct() <= 75) then
        creature:RemoveEventById(event)
        creature:CastSpell(creature:GetVictim(), 40000)
    end
end

function OnLeaveCombat(event, creature)
    creature:RemoveEvents()
    creature:SendUnitYell("Haha, I'm out of combat!", 0)
end

function OnTargetDied(event, creature, target)
    creature:SendUnitYell("I killed you!", 0)
end

function OnDied(event, creature, killer)
    creature:RemoveEvents()
    creature:SendUnitYell("Haha, I'm dead!", 0)
end

RegisterCreatureEvent(npcId, 1, OnEnterCombat)
RegisterCreatureEvent(npcId, 2, OnLeaveCombat)
RegisterCreatureEvent(npcId, 3, OnTargetDied)
RegisterCreatureEvent(npcId, 4, OnDied)
RegisterCreatureEvent(npcId, 23, OnReset)