Prometheus,
If this card is Normal Summoned: Banish 1 or more DARK monsters from your GY, and if you do, this card gains 400 ATK for each, until the end of this turn.
local s, id, o = GetID()
function s.initial_effect(c)
	--atkup
	local e1 = Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id, 0))
	e1:SetCategory(CATEGORY_REMOVE + CATEGORY_ATKCHANGE)
	e1:SetType(EFFECT_TYPE_SINGLE + EFFECT_TYPE_TRIGGER_F)
	e1:SetCode(EVENT_SUMMON_SUCCESS)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
end
function s.cfilter(c)
	return c:IsAttribute(ATTRIBUTE_DARK) and c:IsAbleToRemove()
end
function s.target(e, tp, eg, ep, ev, re, r, rp, chk)
	if chk == 0 then
		return true
	end
	local g = Duel.GetMatchingGroup(s.cfilter, tp, LOCATION_GRAVE, 0, nil)
	if g:GetCount() > 0 then
		Duel.SetOperationInfo(0, CATEGORY_REMOVE, g, 1, tp, LOCATION_GRAVE)
	end
end
function s.operation(e, tp, eg, ep, ev, re, r, rp)
	local c = e:GetHandler()
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_REMOVE)
	local cg = Duel.SelectMatchingCard(tp, s.cfilter, tp, LOCATION_GRAVE, 0, 1, 63, nil)
	local ct = Duel.Remove(cg, POS_FACEUP, REASON_EFFECT)
	if ct > 0 and c:IsFaceup() and c:IsRelateToEffect(e) then
		local e1 = Effect.CreateEffect(c)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_UPDATE_ATTACK)
		e1:SetValue(ct * 400)
		e1:SetReset(RESET_EVENT + RESETS_STANDARD + RESET_DISABLE + RESET_PHASE + PHASE_END, 1)
		c:RegisterEffect(e1)
	end
end


Prometheus,
If this card is Normal Summoned: Banish 1 or more DARK monsters from your GY, and if you do, this card gains 400 ATK for each, until the end of this turn.
-- Prometheus,
local s, id, o = GetID()
function s.initial_effect(c)
	--atkup
	local e1 = Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id, 0))
	e1:SetCategory(CATEGORY_REMOVE + CATEGORY_ATKCHANGE)
	e1:SetType(EFFECT_TYPE_SINGLE + EFFECT_TYPE_TRIGGER_F)
	e1:SetCode(EVENT_SUMMON_SUCCESS)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
end
function s.cfilter(c)
	return c:IsAttribute(ATTRIBUTE_DARK) and c:IsAbleToRemove()
end
function s.target(e, tp, eg, ep, ev, re, r, rp, chk)
	if chk == 0 then
		return true
	end
	local g = Duel.GetMatchingGroup(s.cfilter, tp, LOCATION_GRAVE, 0, nil)
	if g:GetCount() > 0 then
		Duel.SetOperationInfo(0, CATEGORY_REMOVE, g, 1, tp, LOCATION_GRAVE)
	end
end
function s.operation(e, tp, eg, ep, ev, re, r, rp)
	local c = e:GetHandler()
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_REMOVE)
	local cg = Duel.SelectMatchingCard(tp, s.cfilter, tp, LOCATION_GRAVE, 0, 1, 63, nil)
	local ct = Duel.Remove(cg, POS_FACEUP, REASON_EFFECT)
	if ct > 0 and c:IsFaceup() and c:IsRelateToEffect(e) then
		local e1 = Effect.CreateEffect(c)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_UPDATE_ATTACK)
		e1:SetValue(ct * 400)
		e1:SetReset(RESET_EVENT + RESETS_STANDARD + RESET_DISABLE + RESET_PHASE + PHASE_END, 1)
		c:RegisterEffect(e1)
	end
end

