Urgent
Return 1 "Iron Core of Koa'ki Meiru" from your Graveyard to the Deck. Special Summon 1 Level 4 or lower "Koa'ki Meiru" monster from your hand or your Graveyard.
local CARD_ID_0 = 36623431 --Iron Core of Koa'ki Meiru
local SETCARD_ID_0 = 0x1d --Koa'ki

local CARD_ID_0 = 36623431 --Iron Core of Koa'ki Meiru
local SETCARD_ID_0 = 0x1d --Koa'ki
local s, id, o = GetID()
function s.initial_effect(c)
	aux.AddCodeList(c, CARD_ID_0)
	--Activate
	local e1 = Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetCost(s.cost)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
function s.cfilter(c)
	return c:IsCode(CARD_ID_0) and c:IsAbleToDeckAsCost()
end
function s.cost(e, tp, eg, ep, ev, re, r, rp, chk)
	if chk == 0 then
		return Duel.IsExistingMatchingCard(s.cfilter, tp, LOCATION_GRAVE, 0, 1, nil)
	end
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_TODECK)
	local g = Duel.SelectMatchingCard(tp, s.cfilter, tp, LOCATION_GRAVE, 0, 1, 1, nil)
	Duel.SendtoDeck(g, nil, SEQ_DECKSHUFFLE, REASON_COST)
end
function s.spfilter(c, e, tp)
	return c:IsLevelBelow(4) and c:IsSetCard(SETCARD_ID_0) and c:IsCanBeSpecialSummoned(e, 0, tp, false, false)
end
function s.target(e, tp, eg, ep, ev, re, r, rp, chk)
	if chk == 0 then
		return Duel.GetLocationCount(tp, LOCATION_MZONE) > 0 and Duel.IsExistingMatchingCard(s.spfilter, tp, LOCATION_GRAVE + LOCATION_HAND, 0, 1, nil, e, tp)
	end
	Duel.SetOperationInfo(0, CATEGORY_SPECIAL_SUMMON, nil, 1, tp, LOCATION_GRAVE + LOCATION_HAND)
end
function s.activate(e, tp, eg, ep, ev, re, r, rp)
	if Duel.GetLocationCount(tp, LOCATION_MZONE) <= 0 then
		return
	end
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_SPSUMMON)
	local g = Duel.SelectMatchingCard(tp, aux.NecroValleyFilter(s.spfilter), tp, LOCATION_GRAVE + LOCATION_HAND, 0, 1, 1, nil, e, tp)
	if g:GetCount() > 0 then
		Duel.SpecialSummon(g, 0, tp, tp, false, false, POS_FACEUP)
	end
end


Urgent
Return 1 "Iron Core of Koa'ki Meiru" from your Graveyard to the Deck. Special Summon 1 Level 4 or lower "Koa'ki Meiru" monster from your hand or your Graveyard.
-- Urgent
local CARD_ID_0 = 36623431 --Iron Core of Koa'ki Meiru
local SETCARD_ID_0 = 0x1d --Koa'ki
local s, id, o = GetID()
function s.initial_effect(c)
	aux.AddCodeList(c, CARD_ID_0)
	--Activate
	local e1 = Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetCost(s.cost)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
function s.cfilter(c)
	return c:IsCode(CARD_ID_0) and c:IsAbleToDeckAsCost()
end
function s.cost(e, tp, eg, ep, ev, re, r, rp, chk)
	if chk == 0 then
		return Duel.IsExistingMatchingCard(s.cfilter, tp, LOCATION_GRAVE, 0, 1, nil)
	end
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_TODECK)
	local g = Duel.SelectMatchingCard(tp, s.cfilter, tp, LOCATION_GRAVE, 0, 1, 1, nil)
	Duel.SendtoDeck(g, nil, SEQ_DECKSHUFFLE, REASON_COST)
end
function s.spfilter(c, e, tp)
	return c:IsLevelBelow(4) and c:IsSetCard(SETCARD_ID_0) and c:IsCanBeSpecialSummoned(e, 0, tp, false, false)
end
function s.target(e, tp, eg, ep, ev, re, r, rp, chk)
	if chk == 0 then
		return Duel.GetLocationCount(tp, LOCATION_MZONE) > 0 and Duel.IsExistingMatchingCard(s.spfilter, tp, LOCATION_GRAVE + LOCATION_HAND, 0, 1, nil, e, tp)
	end
	Duel.SetOperationInfo(0, CATEGORY_SPECIAL_SUMMON, nil, 1, tp, LOCATION_GRAVE + LOCATION_HAND)
end
function s.activate(e, tp, eg, ep, ev, re, r, rp)
	if Duel.GetLocationCount(tp, LOCATION_MZONE) <= 0 then
		return
	end
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_SPSUMMON)
	local g = Duel.SelectMatchingCard(tp, aux.NecroValleyFilter(s.spfilter), tp, LOCATION_GRAVE + LOCATION_HAND, 0, 1, 1, nil, e, tp)
	if g:GetCount() > 0 then
		Duel.SpecialSummon(g, 0, tp, tp, false, false, POS_FACEUP)
	end
end

