Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
During each of your End Phases, destroy this card unless you send 1 "Iron Core of Koa'ki Meiru" from your hand to the Graveyard. You can Tribute Summon this monster by Tributing 1 "Koa'ki Meiru" monster. This card cannot be destroyed by the effects of Trap Cards. During battle between this attacking card and a Defense Position monster whose DEF is lower than the ATK of this card, inflict the difference as Battle Damage to your opponent.
--コアキメイル・ヴァラファール
--Koa'ki Meiru Valafar
local s,id=GetID()
function s.initial_effect(c)
	--cost
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_FIELD+EFFECT_TYPE_CONTINUOUS)
	e1:SetProperty(EFFECT_FLAG_UNCOPYABLE+EFFECT_FLAG_CANNOT_DISABLE)
	e1:SetCode(EVENT_PHASE+PHASE_END)
	e1:SetCountLimit(1)
	e1:SetRange(LOCATION_MZONE)
	e1:SetCondition(s.mtcon)
	e1:SetOperation(s.mtop)
	c:RegisterEffect(e1)
	--summon with 1 tribute
	local e2=aux.AddNormalSummonProcedure(c,true,true,1,1,SUMMON_TYPE_TRIBUTE,aux.Stringid(id,0),s.otfilter)
	--pierce
	local e3=Effect.CreateEffect(c)
	e3:SetType(EFFECT_TYPE_SINGLE)
	e3:SetCode(EFFECT_PIERCE)
	c:RegisterEffect(e3)
	--indes
	local e4=Effect.CreateEffect(c)
	e4:SetType(EFFECT_TYPE_SINGLE)
	e4:SetCode(EFFECT_INDESTRUCTABLE_EFFECT)
	e4:SetProperty(EFFECT_FLAG_SINGLE_RANGE)
	e4:SetRange(LOCATION_MZONE)
	e4:SetValue(s.efilter)
	c:RegisterEffect(e4)
end
s.listed_series={SET_KOAKI_MEIRU}
s.listed_names={36623431}
function s.mtcon(e,tp,eg,ep,ev,re,r,rp)
	return Duel.IsTurnPlayer(tp)
end
function s.cfilter1(c)
	return c:IsCode(36623431) and c:IsAbleToGraveAsCost()
end
function s.mtop(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	Duel.HintSelection(Group.FromCards(c))
	local g1=Duel.GetMatchingGroup(s.cfilter1,tp,LOCATION_HAND,0,nil)
	local select=1
	if #g1>0 then
		select=Duel.SelectOption(tp,aux.Stringid(id,0),aux.Stringid(id,1))
	else
		select=Duel.SelectOption(tp,aux.Stringid(id,1))+1
	end
	if select==0 then
		Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_TOGRAVE)
		local g=g1:Select(tp,1,1,nil)
		Duel.SendtoGrave(g,REASON_COST)
	else
		Duel.Destroy(c,REASON_COST)
	end
end
function s.otfilter(c,tp)
	return c:IsSetCard(SET_KOAKI_MEIRU) and (c:IsControler(tp) or c:IsFaceup())
end
function s.efilter(e,re,rp)
	return re:IsTrapEffect()
end