Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
You can discard this card; add 1 "Labyrinth Wall" card from your Deck to your hand. At the start of the Damage Step, if your opponent's monster battles, while you control a "Labyrinth Wall" card: You can banish this card from your GY; destroy that opponent's monster. You can only use each effect of "Shadow Ghoul of the Labyrinth" once per turn.
--迷宮に潜むシャドウ・グール
--Shadow Ghoul of the Labyrinth
--Scripted by Satella
local s,id=GetID()
function s.initial_effect(c)
	--Search 1 "Labyrinth Wall" card
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_TOHAND+CATEGORY_SEARCH)
	e1:SetType(EFFECT_TYPE_IGNITION)
	e1:SetRange(LOCATION_HAND)
	e1:SetCountLimit(1,id)
	e1:SetCost(Cost.SelfDiscard)
	e1:SetTarget(s.thtg)
	e1:SetOperation(s.thop)
	c:RegisterEffect(e1)
	--Destroy 1 opponent's battling monster
	local e2=Effect.CreateEffect(c)
	e2:SetDescription(aux.Stringid(id,1))
	e2:SetCategory(CATEGORY_DESTROY)
	e2:SetType(EFFECT_TYPE_FIELD+EFFECT_TYPE_TRIGGER_O)
	e2:SetCode(EVENT_BATTLE_START)
	e2:SetRange(LOCATION_GRAVE)
	e2:SetCountLimit(1,{id,1})
	e2:SetCondition(s.descon)
	e2:SetCost(Cost.SelfBanish)
	e2:SetTarget(s.destg)
	e2:SetOperation(s.desop)
	c:RegisterEffect(e2)
end
s.listed_seires={SET_LABYRINTH_WALL}
function s.thfilter(c)
	return c:IsSetCard(SET_LABYRINTH_WALL) and c:IsAbleToHand()
end
function s.thtg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.thfilter,tp,LOCATION_DECK,0,1,nil) end
	Duel.SetOperationInfo(0,CATEGORY_TOHAND,nil,1,tp,LOCATION_DECK)
end
function s.thop(e,tp,eg,ep,ev,re,r,rp)
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_ATOHAND)
	local g=Duel.SelectMatchingCard(tp,s.thfilter,tp,LOCATION_DECK,0,1,1,nil)
	if #g>0 then
		Duel.SendtoHand(g,nil,REASON_EFFECT)
		Duel.ConfirmCards(1-tp,g)
	end
end
function s.descon(e,tp,eg,ep,ev,re,r,rp)
	return Duel.GetBattleMonster(1-tp) and Duel.IsExistingMatchingCard(aux.FaceupFilter(Card.IsSetCard,SET_LABYRINTH_WALL),tp,LOCATION_ONFIELD,0,1,nil)
end
function s.destg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return true end
	Duel.SetOperationInfo(0,CATEGORY_DESTROY,Duel.GetBattleMonster(1-tp),1,0,0)
end
function s.desop(e,tp,eg,ep,ev,re,r,rp)
	local tc=Duel.GetBattleMonster(1-tp)
	if tc and tc:IsRelateToBattle() then
		Duel.Destroy(tc,REASON_EFFECT)
	end
end