--Subterror Behemoth Voltelluric
function c21607304.initial_effect(c)
	--flip
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(21607304,0))
	e1:SetCategory(CATEGORY_CONTROL)
	e1:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_FLIP+EFFECT_TYPE_TRIGGER_O)
	e1:SetProperty(EFFECT_FLAG_DELAY+EFFECT_FLAG_CARD_TARGET)
	e1:SetCountLimit(1,21607304)
	e1:SetTarget(c21607304.target)
	e1:SetOperation(c21607304.operation)
	c:RegisterEffect(e1)
	--special summon
	local e2=Effect.CreateEffect(c)
	e2:SetDescription(aux.Stringid(21607304,1))
	e2:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e2:SetType(EFFECT_TYPE_FIELD+EFFECT_TYPE_TRIGGER_O)
	e2:SetRange(LOCATION_HAND)
	e2:SetCode(EVENT_CHANGE_POS)
	e2:SetCondition(c21607304.spcon)
	e2:SetTarget(c21607304.sptg)
	e2:SetOperation(c21607304.spop)
	c:RegisterEffect(e2)
	--turn set
	local e3=Effect.CreateEffect(c)
	e3:SetDescription(aux.Stringid(21607304,2))
	e3:SetCategory(CATEGORY_POSITION)
	e3:SetType(EFFECT_TYPE_IGNITION)
	e3:SetRange(LOCATION_MZONE)
	e3:SetTarget(c21607304.postg)
	e3:SetOperation(c21607304.posop)
	c:RegisterEffect(e3)
end
function c21607304.filter(c)
	return c:IsFacedown() and c:IsControlerCanBeChanged()
end
function c21607304.target(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
	if chkc then return chkc:IsLocation(LOCATION_MZONE) and chkc:IsControler(1-tp) and c21607304.filter(chkc) end
	if chk==0 then return Duel.IsExistingTarget(c21607304.filter,tp,0,LOCATION_MZONE,1,nil) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_CONTROL)
	local g=Duel.SelectTarget(tp,c21607304.filter,tp,0,LOCATION_MZONE,1,1,nil)
	Duel.SetOperationInfo(0,CATEGORY_CONTROL,g,1,0,0)
end
function c21607304.operation(e,tp,eg,ep,ev,re,r,rp)
	local tc=Duel.GetFirstTarget()
	local tct=1
	if Duel.GetTurnPlayer()~=tp then tct=2
	elseif Duel.GetCurrentPhase()==PHASE_END then tct=3 end
	if tc:IsFacedown() and tc:IsRelateToEffect(e) then
		Duel.GetControl(tc,tp,PHASE_END,tct)
	end
end
function c21607304.cfilter(c,tp)
	return c:IsPreviousPosition(POS_FACEUP) and c:IsFacedown() and c:IsControler(tp)
end
function c21607304.spcon(e,tp,eg,ep,ev,re,r,rp)
	return eg:IsExists(c21607304.cfilter,1,nil,tp)
		and not Duel.IsExistingMatchingCard(Card.IsFaceup,tp,LOCATION_MZONE,0,1,nil)
end
function c21607304.sptg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.GetLocationCount(tp,LOCATION_MZONE)>0
		and e:GetHandler():IsCanBeSpecialSummoned(e,0,tp,false,false,POS_FACEUP_DEFENSE) end
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,e:GetHandler(),1,0,0)
end
function c21607304.spop(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	if not c:IsRelateToEffect(e) then return end
	Duel.SpecialSummon(c,0,tp,tp,false,false,POS_FACEUP_DEFENSE)
end
function c21607304.postg(e,tp,eg,ep,ev,re,r,rp,chk)
	local c=e:GetHandler()
	if chk==0 then return c:IsCanTurnSet() and c:GetFlagEffect(21607304)==0 end
	c:RegisterFlagEffect(21607304,RESET_EVENT+0x1fc0000+RESET_PHASE+PHASE_END,0,1)
	Duel.SetOperationInfo(0,CATEGORY_POSITION,c,1,0,0)
end
function c21607304.posop(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	if c:IsRelateToEffect(e) and c:IsFaceup() then
		Duel.ChangePosition(c,POS_FACEDOWN_DEFENSE)
	end
end
