Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
2 Level 4 EARTH monsters Once per turn: You can detach 1 Xyz Material from this card; all non-EARTH monsters currently on the field lose 500 ATK and DEF.
--妖精王 アルヴェルド
--Fairy King Albverdich
local s,id=GetID()
function s.initial_effect(c)
	c:EnableReviveLimit()
	--Xyz Summon procedure
	Xyz.AddProcedure(c,aux.FilterBoolFunctionEx(Card.IsAttribute,ATTRIBUTE_EARTH),4,2)
	--Non-EARTH monsters lose 500 ATK/DEF
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_ATKCHANGE+CATEGORY_DEFCHANGE)
	e1:SetType(EFFECT_TYPE_IGNITION)
	e1:SetRange(LOCATION_MZONE)
	e1:SetCountLimit(1)
	e1:SetCost(Cost.DetachFromSelf(1,1,nil))
	e1:SetTarget(s.adtg)
	e1:SetOperation(s.adop)
	c:RegisterEffect(e1)
end
function s.adtg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(aux.FaceupFilter(Card.IsAttributeExcept,ATTRIBUTE_EARTH),tp,LOCATION_MZONE,LOCATION_MZONE,1,nil) end
end
function s.adop(e,tp,eg,ep,ev,re,r,rp)
	local g=Duel.GetMatchingGroup(aux.FaceupFilter(Card.IsAttributeExcept,ATTRIBUTE_EARTH),tp,LOCATION_MZONE,LOCATION_MZONE,nil)
	if #g==0 then return end
	local c=e:GetHandler()
	for tc in g:Iter() do
		--Decrease ATK/DEF
		local e1=Effect.CreateEffect(c)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetProperty(EFFECT_FLAG_CANNOT_DISABLE)
		e1:SetCode(EFFECT_UPDATE_ATTACK)
		e1:SetValue(-500)
		e1:SetReset(RESET_EVENT|RESETS_STANDARD)
		tc:RegisterEffect(e1)
		local e2=e1:Clone()
		e2:SetCode(EFFECT_UPDATE_DEFENSE)
		tc:RegisterEffect(e2)
	end
end