Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
2 Level 4 DARK monsters Once per turn (Quick Effect): You can detach 1 material from this card; this face-up card is unaffected by other monster effects this turn.
--ヴェルズ・タナトス
--Evilswarm Thanatos
local s,id=GetID()
function s.initial_effect(c)
	--Must be properly summoned before reviving
	c:EnableReviveLimit()
	--Xyz summon procedure
	Xyz.AddProcedure(c,aux.FilterBoolFunctionEx(Card.IsAttribute,ATTRIBUTE_DARK),4,2)
	--Make itself unaffected by monster effects
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetType(EFFECT_TYPE_QUICK_O)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetCountLimit(1)
	e1:SetRange(LOCATION_MZONE)
	e1:SetCost(Cost.DetachFromSelf(1))
	e1:SetOperation(s.operation)
	e1:SetHintTiming(0,TIMINGS_CHECK_MONSTER|TIMING_END_PHASE)
	c:RegisterEffect(e1)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	if c:IsFaceup() and c:IsRelateToEffect(e) then
		--Unaffected by monster effects
		local e1=Effect.CreateEffect(c)
		e1:SetDescription(3101)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetProperty(EFFECT_FLAG_SINGLE_RANGE+EFFECT_FLAG_CLIENT_HINT)
		e1:SetRange(LOCATION_MZONE)
		e1:SetCode(EFFECT_IMMUNE_EFFECT)
		e1:SetReset(RESETS_STANDARD_PHASE_END)
		e1:SetValue(s.efilter)
		c:RegisterEffect(e1)
	end
end
function s.efilter(e,te)
	return te:IsActiveType(TYPE_EFFECT) and te:GetOwner()~=e:GetOwner()
end