[Lua] Need script help!

[jarjarb14]

So, below is my boss. As a precaution, this is my first script so I'm assuming there are going to be various errors. And boy are there errors...
My biggest issue is that phase two of my boss just doesn't work. I've been changing things around for a while with no luck.

--[[
                Archaeon Boss Script
                Written by: Jarjarb

                Phase 1: Saber Lash attack (every 5 secs) and shadowbolt volley (every 10 secs)
                         35 secs later
                Phase 2: Random planned is stunned and DoT'd. Boss gets shield.
                         Boss stops DoT only if shield is broken, 31 secs have passed, or player has died.
                         Return to Phase 1. Unless...
                Phase 3: Boss is at <20% health. Boss Enrages. Two adds spawned (Unstable Arcanoids) which move slowly and
			 cast Arcane explosion every 2 seconds. These must be OT'd and kept away from party. More damage done to them, the faster they go.

                Enjoy!
--]]

-- On Triggers

function Archaeon_OnCombat(pUnit, Event)
        pUnit:SendChatMessage(14, 0, "You dare attack an Ambasador of Arcana?! Meet your end!")
        pUnit:RegisterEvent("Archaeon_Phase1", 2000, 0)
end

function Archaeon_LeaveCombat(pUnit, Event)
        pUnit:RemoveEvents()
        pUnit:SendChatMessage(12, 0, "Fools...")
end

function Archaeon_Kill(pUnit, Event)
        local chatrandom = math.random(1, 3)
		if (chatrandom == 1) then
			pUnit:SendChatMessage(12, 0, "Hahahahaha!")
		elseif (chatrandom == 2) then
			pUnit:SendChatMessage(12, 0, "Pathetic...")
		elseif (chatrandom == 3) then
			pUnit:SendchatMessage(12, 0, "A waste of my time...")
		end
end

function Archaeon_Dead(pUnit, Event)
        pUnit:RemoveEvents()
        pUnit:SendChatMessage(12, 0, "What have you done....my people shall here of this...they will.....")
end

RegisterUnitEvent(40013, 1, "Archaeon_OnCombat")
RegisterUnitEvent(40013, 2, "Archaeon_LeaveCombat")
RegisterUnitEvent(40013, 3, "Archaeon_Kill")
RegisterUnitEvent(40013, 4, "Archaeon_Dead")

------------------------------------------------------------------------Phase 1

function Archaeon_Phase1(pUnit, Event)
        pUnit:RemoveEvents()
        pUnit:RegisterEvent("Archaeon_Phase3", 1000, 0)
        pUnit:RegisterEvent("Archaeon_Phase2", 35000, 1)
        pUnit:SendBroadcastMessage("PHASE 1")
		pUnit:RegisterEvent("Archaeon_SaberLash", 5000, 0)
        pUnit:RegisterEvent("Archaeon_ShadowVolley", 10000, 0)
end

------------------------------------------------------------------------Spells for Phase 1
function Archaeon_SaberLash(pUnit, Event)
        pUnit:CastSpellOnTarget(43267, pUnit:GetMainTank())
end

function Archaeon_ShadowVolley(pUnit, Event)
        pUnit:CastSpellOnTarget(55323, pUnit:GetMainTank())
end

-------------------------------------------------------------------------Phase 2
function Archaeon_Phase2(pUnit, Event)
        pUnit:RemoveEvents()
		pUnit:CastSpell(71781)
		pUnit:SendBroadcastMessage("PHASE 2")
		pUnit:RegisterEvent("Archaeon_Phase1", 31000, 1)
        pUnit:RegisterEvent("Archaeon_AuraCheck", 100, 0)
		pUnit:RegisterEvent("Archaeon_DrainAttack", 100, 1)
end


function Archaeon_DrainAttack(pUnit, target, Event)
	if (target ~= nil) then
	local target = pUnit:GetRandomPlayer(0)
	local class = target:GetPlayerClass()
	pUnit:ChannelSpell(target:GetGUID(),46466)
	target:SendBroadcastMessage("Your life is mine!")
	end
	local x = pUnit:GetX()
	local y = pUnit:GetY()
	local z = pUnit:GetZ()
	local o = pUnit:GetO()
	local yfly = y + 2
	local zfly = z + 2
	target:MovePlayerTo(x, yfly, zfly, o, 256)
	target:SetPlayerLock(true)
	if (class == 1) then
			pUnit:SendChatMessage(11, 0, "Pitiful Warrior... all brawn and no brains...")
		elseif (class == 2) then
			pUnit:SendChatMessage(11, 0, "Your faith in the Light shall be your undoing!")
		elseif (class == 3) then
			pUnit:SendChatMessage(11, 0, "Your primitive mind bores me.")
		elseif (class == 4) then
			pUnit:SendChatMessage(11, 0, "What have we here? A pest that shall be dealt with!")
		elseif (class == 5) then
			pUnit:SendChatMessage(11, 0, "Say your last prayers, Priest. Not that they'll help you...")
		elseif (class == 6) then
			pUnit:SendChatMessage(11, 0, "A former pawn of the Lich King... You shall die once more!")
		elseif (class == 7) then
			pUnit:SendChatMessage(11, 0, "Your Spirits won't save you now! Die worm!")
		elseif (class == 8) then
			pUnit:SendChatMessage(11, 0, "Tsk tsk... You have so much potential, Mage. Such a shame that you waste it on these so called friends.")
		elseif (class == 9) then
			pUnit:SendChatMessage(11, 0, "Your trust in daemon magic is astounding considering how weak it is compared to the magic of my people...")
		elseif (class == 11) then
			pUnit:SendChatMessage(11, 0, "Nature won't save you now, Child of Cenarius. Prepare to meet your doom.")
		end
end

function Archaeon_AuraCheck(pUnit, target, Event)              --This is to check whether the Shield Aura has been destroyed.
        if (pUnit:HasAura(71781) == false) then
		target:SetPlayerLock(false)
		pUnit:StopChannel()
		pUnit:RemoveEvents()
		pUnit:RegisterEvent("Archaeon_Phase1", 100, 0)
        end
end

-------------------------------------------------------------------------Phase 3
function Archaeon_Phase3(pUnit, Event)
        if (pUnit:GetHealthPct() <= 20) then
                pUnit:RemoveEvents()
                pUnit:SendBroadcastMessage("PHASE 3")
				pUnit:CastSpell(68335)
                pUnit:SendChatMessage(12, 0, "ENOUGH! We finish this now! Brothers, assist me!")
                pUnit:RegisterEvent("Archeaon_SaberLash", 6000, 0)
				local xx = pUnit:GetX()
				local yy = pUnit:GetY()
				local zz = pUnit:GetZ()
				local xa = xx + 2
				local xb = xx - 2
				pUnit:SpawnCreature(40014,xa,yy,zz,14)
				pUnit:SpawnCreature(40014,xb,yy,zz,14)
                end
end

My plan is to have him shield himself, cause a player to be ported into the air while he channels a spell on them. The only way to rescue the person is to wait till the shield runs out or to destroy the shield. DPS is the name of the game.

Feel free to mock my script. I actually want some criticism so fire away!

And if you like the script, feel free to use it. Just gotta fix it! :P

Thanks in advance

[stoneharry]

The only thing I see from quickly reading through it is a few syntex's are wrong (e.g: SpawnCreature(id,x,y,z,o,faction,time) you just have x y z faction) and you don't check to see if everything is there which could cause errors (get class -> would if the player was nil?).