Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
You can Special Summon this card (from your hand or GY) by Tributing 1 monster on either player's field with a Predator Counter. You can only Special Summon "Predaplant Drosophyllum Hydra" once per turn this way. If this card is on the field or in your GY (Quick Effect): You can banish 1 other "Predaplant" monster from your GY, then target 1 face-up monster on the field; it loses 500 ATK. You can only use this effect of "Predaplant Drosophyllum Hydra" once per turn.
--捕食植物ドロソフィルム・ヒドラ
--Predaplant Drosophyllum Hydra
local s,id=GetID()
function s.initial_effect(c)
	--special summon rule
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_FIELD)
	e1:SetCode(EFFECT_SPSUMMON_PROC)
	e1:SetRange(LOCATION_HAND|LOCATION_GRAVE)
	e1:SetProperty(EFFECT_FLAG_UNCOPYABLE)
	e1:SetCountLimit(1,id,EFFECT_COUNT_CODE_OATH)
	e1:SetCondition(s.hspcon)
	e1:SetTarget(s.hsptg)
	e1:SetOperation(s.hspop)
	c:RegisterEffect(e1)
	--decrease atk
	local e2=Effect.CreateEffect(c)
	e2:SetDescription(aux.Stringid(id,0))
	e2:SetCategory(CATEGORY_ATKCHANGE)
	e2:SetType(EFFECT_TYPE_QUICK_O)
	e2:SetCode(EVENT_FREE_CHAIN)
	e2:SetProperty(EFFECT_FLAG_DAMAGE_STEP+EFFECT_FLAG_CARD_TARGET)
	e2:SetRange(LOCATION_MZONE|LOCATION_GRAVE)
	e2:SetCountLimit(1,{id,1})
	e2:SetCost(s.atkcost)
	e2:SetTarget(s.atktg)
	e2:SetOperation(s.atkop)
	c:RegisterEffect(e2)
end
s.counter_list={COUNTER_PREDATOR}
s.listed_series={SET_PREDAPLANT}
function s.hspfilter(c,ft,tp)
	return c:GetCounter(COUNTER_PREDATOR)>0 and c:IsReleasable() and (ft>0 or (c:GetSequence()<5 and c:IsControler(tp))) and (c:IsFaceup() or c:IsControler(tp))
end
function s.hspcon(e,c)
	if c==nil then return true end
	local eff={c:GetCardEffect(EFFECT_NECRO_VALLEY)}
	for _,te in ipairs(eff) do
		local op=te:GetOperation()
		if not op or op(e,c) then return false end
	end
	local tp=c:GetControler()
	local ft=Duel.GetLocationCount(tp,LOCATION_MZONE)
	local rg=Duel.GetMatchingGroup(s.hspfilter,tp,LOCATION_MZONE,LOCATION_MZONE,nil,ft,tp)
	return ft>-1 and #rg>0 and aux.SelectUnselectGroup(rg,e,tp,1,1,nil,0)
end
function s.hsptg(e,tp,eg,ep,ev,re,r,rp,c)
	local c=e:GetHandler()
	local g=nil
	local ft=Duel.GetLocationCount(tp,LOCATION_MZONE)
	local rg=Duel.GetMatchingGroup(s.hspfilter,tp,LOCATION_MZONE,LOCATION_MZONE,nil,ft,tp)
	local g=aux.SelectUnselectGroup(rg,e,tp,1,1,nil,1,tp,HINTMSG_RELEASE,nil,nil,true)
	if #g>0 then
		g:KeepAlive()
		e:SetLabelObject(g)
		return true
	end
	return false
end
function s.hspop(e,tp,eg,ep,ev,re,r,rp,c)
	local g=e:GetLabelObject()
	if not g then return end
	Duel.Release(g,REASON_COST)
	g:DeleteGroup()
end
function s.atkcfil(c)
	return c:IsSetCard(SET_PREDAPLANT) and c:IsMonster() and c:IsAbleToRemoveAsCost() and aux.SpElimFilter(c,true) 
		and Duel.IsExistingTarget(Card.IsFaceup,0,LOCATION_MZONE,LOCATION_MZONE,1,c)
end
function s.atkcost(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.atkcfil,tp,LOCATION_MZONE|LOCATION_GRAVE,0,1,e:GetHandler()) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_REMOVE)
	local g=Duel.SelectMatchingCard(tp,s.atkcfil,tp,LOCATION_MZONE|LOCATION_GRAVE,0,1,1,e:GetHandler())
	Duel.Remove(g,POS_FACEUP,REASON_COST)
end
function s.atktg(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
	if chkc then return chkc:IsLocation(LOCATION_MZONE) and chkc:IsFaceup() end
	if chk==0 then return Duel.IsExistingTarget(Card.IsFaceup,tp,LOCATION_MZONE,LOCATION_MZONE,1,nil) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_TARGET)
	Duel.SelectTarget(tp,Card.IsFaceup,tp,LOCATION_MZONE,LOCATION_MZONE,1,1,nil)
end
function s.atkop(e,tp,eg,ep,ev,re,r,rp)
	local tc=Duel.GetFirstTarget()
	if tc and tc:IsFaceup() and tc:IsRelateToEffect(e) then
		local e1=Effect.CreateEffect(e:GetHandler())
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_UPDATE_ATTACK)
		e1:SetValue(-500)
		e1:SetReset(RESET_EVENT|RESETS_STANDARD)
		tc:RegisterEffect(e1)
	end
end