Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If this card is in your hand or GY: You can target 1 face-up monster on each field; change them to face-down Defense Position, and if you do, Special Summon this card, but banish it when it leaves the field. You can only use this effect of "Ret-time Reviver Emit-ter" once per turn.
--生きる偲びのシルキィ
--Ret-time Reviver Emit-ter
--Scripted by AlphaKretin
local s,id=GetID()
function s.initial_effect(c)
	--Special summon itself from hand or GY
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_POSITION+CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_IGNITION)
	e1:SetProperty(EFFECT_FLAG_CARD_TARGET)
	e1:SetRange(LOCATION_HAND|LOCATION_GRAVE)
	e1:SetCountLimit(1,id)
	e1:SetTarget(s.sptg)
	e1:SetOperation(s.spop)
	c:RegisterEffect(e1)
end
function s.posfilter(c)
	return c:IsFaceup() and c:IsCanTurnSet()
end
function s.sptg(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
	local c=e:GetHandler()
	if chkc then return chkc:IsLocation(LOCATION_MZONE) and s.filter(chkc) end
	if chk==0 then return Duel.GetLocationCount(tp,LOCATION_MZONE)>0
		and c:IsCanBeSpecialSummoned(e,0,tp,false,false)
		and Duel.IsExistingTarget(s.posfilter,tp,LOCATION_MZONE,0,1,nil) and Duel.IsExistingTarget(s.posfilter,tp,0,LOCATION_MZONE,1,nil) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_POSCHANGE)
	local g1=Duel.SelectTarget(tp,s.posfilter,tp,LOCATION_MZONE,0,1,1,nil)
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_POSCHANGE)
	local g2=Duel.SelectTarget(tp,s.posfilter,tp,0,LOCATION_MZONE,1,1,nil)
	g1:Merge(g2)
	Duel.SetOperationInfo(0,CATEGORY_POSITION,g1,2,0,0)
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,c,1,0,0)
end
function s.spop(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	local g=Duel.GetTargetCards(e):Filter(Card.IsFaceup,nil)
	if #g>0 and Duel.ChangePosition(g,POS_FACEDOWN_DEFENSE)>0 then
		if c:IsRelateToEffect(e) and Duel.SpecialSummon(c,0,tp,tp,false,false,POS_FACEUP)~=0 then
			--Banish it if it leaves the field
			local e1=Effect.CreateEffect(c)
			e1:SetDescription(3300)
			e1:SetType(EFFECT_TYPE_SINGLE)
			e1:SetCode(EFFECT_LEAVE_FIELD_REDIRECT)
			e1:SetProperty(EFFECT_FLAG_CANNOT_DISABLE+EFFECT_FLAG_CLIENT_HINT)
			e1:SetReset(RESET_EVENT|RESETS_REDIRECT)
			e1:SetValue(LOCATION_REMOVED)
			c:RegisterEffect(e1)
		end
	end
end