Cooldowns on Spells?

[choweyiii]

I made a boss, but he just spams 1 spell over and over until he's low on mana, which triggers some phases, how can I add a cooldown to the spell, to make him more mana efficient? +Rep for anyone who can help. :]

Here's the script so far:

function AllianceElemental_OnCombat(Unit, Event)
Unit:CastSpellAoF(Unit:GetX(), Unit:GetY(), Unit:GetZ(), 26607)
Unit:RegisterEvent("AllianceElemental_FrostNova", 1000, 0)
Unit:RegisterEvent("AllianceElemental_FrostBolt", 1000, 0)
Unit:RegisterEvent("AllianceElemental_OoM", 1000, 0)
end

function AllianceElemental_OoM(Unit, Event)
	if Unit:GetManaPct() <= 10 then
		Unit:SendChatMessage(12, 0, "|cFF000000Out of Mana! :( Don't hurt me while I regain it.")
		Unit:CastSpell(30254)
		Unit:CastSpell(31539)
		Unit:RegisterEvent("AllianceElemental_Restored_Mana",1000 ,0)
		end
end

function AllianceElemental_Restored_Mana(Unit, Event)
	if Unit:GetManaPct() >= 99 then
		Unit:CastSpell(31249)
		Unit:SendChatMessage(12, 0, "|cFF000000Yay! My mana has been restored! :>")
		Unit:RemoveAura(30254)
		Unit:RemoveAura(31539)
		Unit:RegisterEvent("AllianceElemental_FrostBolt", 1000, 0)
		end
end

function AllianceElemental_FrostBolt(Unit, Event)
Unit:CastSpellOnTarget(31249)  -- This is the spell I want a cool down on.
Unit:WipeTargetList()
Unit:ClearHateList()
end

function AllianceElemental_FrostNova(Unit, Event)
	if Unit:GetHealthPct() <= 38 then
		Unit:FullCastSpellOnTarget(31249, Unit:GetMainTank(0))
		Unit:CastSpell(72259)
	end
end

function AllianceElemental_OnDied(Unit, Event)
Unit:ReturnToSpawnPoint()
Unit:Despawn(6000, 3500)
Unit:SendChatMessage(12, 0, "|cFFFF3300Ouch! |cFF000000Why?...")
end

function AllianceElemental_OnKilledTarget(Unit, Event)
Unit:CastSpell(43186)
Unit:CastSpell(43186)
end

RegisterUnitEvent(10955, 1, "AllianceElemental_OnCombat")
RegisterUnitEvent(10955, 4, "AllianceElemental_OnDied")
RegisterUnitEvent(10955, 3, "AllianceElemental_OnKilledTarget")

[Pharcide]

Unit:RegisterEvent("AllianceElemental_FrostNova", 1000, 0)

that value in red is how often the function is called (in milliseconds), so just raise if you want it to happen in larger intervals

[choweyiii]

Thanks! +Rep