Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
You can Special Summon this card (from your hand) to your opponent's field in Attack Position, by Tributing 1 monster they control. If your opponent controls a "Kaiju" monster, you can Special Summon this card (from your hand) in Attack Position. You can only control 1 "Kaiju" monster. Once per turn (Quick Effect): You can remove 3 Kaiju Counters from anywhere on the field; the ATK/DEF of all other monsters on the field become halved.
--怪粉壊獣ガダーラ
--Gadarla, the Mystery Dust Kaiju
local s,id=GetID()
function s.initial_effect(c)
	local e1,e2=aux.AddKaijuProcedure(c)
	--Halve ATK
	local e3=Effect.CreateEffect(c)
	e3:SetDescription(aux.Stringid(id,0))
	e3:SetCategory(CATEGORY_ATKCHANGE+CATEGORY_DEFCHANGE)
	e3:SetType(EFFECT_TYPE_QUICK_O)
	e3:SetCode(EVENT_FREE_CHAIN)
	e3:SetRange(LOCATION_MZONE)
	e3:SetProperty(EFFECT_FLAG_DAMAGE_STEP)
	e3:SetHintTiming(TIMING_DAMAGE_STEP,TIMING_DAMAGE_STEP|TIMINGS_CHECK_MONSTER)
	e3:SetCountLimit(1)
	e3:SetCondition(aux.StatChangeDamageStepCondition)
	e3:SetCost(s.atkcost)
	e3:SetTarget(s.atktg)
	e3:SetOperation(s.atkop)
	c:RegisterEffect(e3)
end
s.counter_list={COUNTER_KAIJU}
function s.atkcost(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsCanRemoveCounter(tp,1,1,COUNTER_KAIJU,3,REASON_COST) end
	Duel.RemoveCounter(tp,1,1,COUNTER_KAIJU,3,REASON_COST)
end
function s.atktg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(Card.IsFaceup,tp,LOCATION_MZONE,LOCATION_MZONE,1,e:GetHandler()) end
end
function s.atkop(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	local tg=Duel.GetMatchingGroup(Card.IsFaceup,tp,LOCATION_MZONE,LOCATION_MZONE,c)
	local tc=tg:GetFirst()
	for tc in aux.Next(tg) do
		local atk=tc:GetAttack()
		local def=tc:GetDefense()
		local e1=Effect.CreateEffect(c)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_SET_ATTACK_FINAL)
		e1:SetValue(atk/2)
		e1:SetReset(RESET_EVENT|RESETS_STANDARD)
		tc:RegisterEffect(e1)
		local e2=Effect.CreateEffect(c)
		e2:SetType(EFFECT_TYPE_SINGLE)
		e2:SetCode(EFFECT_SET_DEFENSE_FINAL)
		e2:SetValue(def/2)
		e2:SetReset(RESET_EVENT|RESETS_STANDARD)
		tc:RegisterEffect(e2)
	end
end