Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
When this card is discarded to the GY: You can Special Summon it in face-down Defense Position. When this card is flipped face-up: You can reveal 1 "Fabled" monster in your hand; send 1 "Fabled" monster from your Deck to the GY.
--魔轟神獣ペガラサス
--The Fabled Peggulsus
local s,id=GetID()
function s.initial_effect(c)
	--Special summon itself from the GY
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_O)
	e1:SetCode(EVENT_TO_GRAVE)
	e1:SetCondition(s.spcon)
	e1:SetTarget(s.sptg)
	e1:SetOperation(s.spop)
	c:RegisterEffect(e1)
	--Send card to the GY
	local e2=Effect.CreateEffect(c)
	e2:SetDescription(aux.Stringid(id,1))
	e2:SetCategory(CATEGORY_TOGRAVE)
	e2:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_O)
	e2:SetProperty(EFFECT_FLAG_DAMAGE_STEP)
	e2:SetCode(EVENT_FLIP)
	e2:SetCost(s.cost2)
	e2:SetTarget(s.tg2)
	e2:SetOperation(s.op2)
	c:RegisterEffect(e2)
end
s.listed_series={SET_FABLED}
function s.spcon(e,tp,eg,ep,ev,re,r,rp)
	return e:GetHandler():IsPreviousLocation(LOCATION_HAND) and (r&REASON_DISCARD)~=0
end
function s.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_FACEDOWN_DEFENSE) end
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,e:GetHandler(),1,0,0)
end
function s.spop(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	if c:IsRelateToEffect(e) then
		Duel.SpecialSummon(c,0,tp,tp,false,false,POS_FACEDOWN_DEFENSE)
		Duel.ConfirmCards(1-tp,c)
	end
end
function s.cfilter(c)
	return c:IsSetCard(SET_FABLED) and c:IsMonster() and not c:IsPublic()
end
function s.cost2(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.cfilter,tp,LOCATION_HAND,0,1,nil) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_CONFIRM)
	local g=Duel.SelectMatchingCard(tp,s.cfilter,tp,LOCATION_HAND,0,1,1,nil)
	Duel.ConfirmCards(1-tp,g)
	Duel.ShuffleHand(tp)
end
function s.filter2(c)
	return c:IsSetCard(SET_FABLED) and c:IsMonster() and c:IsAbleToGrave()
end
function s.tg2(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.filter2,tp,LOCATION_DECK,0,1,nil) end
	Duel.SetOperationInfo(0,CATEGORY_TOGRAVE,nil,1,tp,LOCATION_DECK)
end
function s.op2(e,tp,eg,ep,ev,re,r,rp)
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_TOGRAVE)
	local g=Duel.SelectMatchingCard(tp,s.filter2,tp,LOCATION_DECK,0,1,1,nil)
	if #g>0 then
		Duel.SendtoGrave(g,REASON_EFFECT)
	end
end