Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
All face-up "Laval" monsters you control gain 100 ATK for each "Laval" monster in your Graveyard.
--炎熱旋風壁
--Molten Whirlwind Wall
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetProperty(EFFECT_FLAG_DAMAGE_STEP)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetHintTiming(TIMING_DAMAGE_STEP)
	e1:SetCondition(aux.StatChangeDamageStepCondition)
	c:RegisterEffect(e1)
	--atk up
	local e2=Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_FIELD)
	e2:SetCode(EFFECT_UPDATE_ATTACK)
	e2:SetRange(LOCATION_SZONE)
	e2:SetTargetRange(LOCATION_MZONE,0)
	e2:SetTarget(aux.TargetBoolFunction(Card.IsSetCard,SET_LAVAL))
	e2:SetValue(s.val)
	c:RegisterEffect(e2)
end
s.listed_series={SET_LAVAL}
function s.val(e,c)
	return Duel.GetMatchingGroupCount(Card.IsSetCard,c:GetControler(),LOCATION_GRAVE,0,nil,SET_LAVAL)*100
end