Magia relampago

Here's a code snippet that should do what you're asking for:

```lua
local s,id,o=GetID()
function s.initial_effect(c)
    local e1=Effect.CreateEffect(c)
    e1:SetType(EFFECT_TYPE_ACTIVATE)
    e1:SetCode(EVENT_FREE_CHAIN)
    e1:SetCondition(s.condition)
    e1:SetTarget(s.target)
    e1:SetOperation(s.activate)
    c:RegisterEffect(e1)
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
    return not Duel.IsExistingMatchingCard(aux.FilterFaceupFunction(Card.IsSetCard,0x123),tp,0,LOCATION_MZONE,1,nil) -- 0x123 is the setcode for "titan" monsters
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
    if chk==0 then return Duel.IsExistingMatchingCard(s.filter,tp,LOCATION_DECK,0,1,nil) end
end
function s.filter(c)
    return c:IsSetCard(0x456) and c:IsAbleToHand() -- 0x456 is the setcode for "lightning" cards
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
    Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_ATOHAND)
    local g=Duel.SelectMatchingCard(tp,s.filter,tp,LOCATION_DECK,0,1,1,nil)
    if #g>0 then
        Duel.SendtoHand(g,nil,REASON_EFFECT)
        Duel.ConfirmCards(1-tp,g)
        if g:GetFirst():IsCode(10000000) then -- 10000000 is the card code for "lightning-Maria"
            Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_REMOVE)
            local g=Duel.SelectMatchingCard(tp,Card.IsFacedown,tp,0,LOCATION_ONFIELD,1,1,nil)
            if #g>0 then
                Duel.Remove(g,POS_FACEDOWN,REASON_EFFECT)
            end
        end
    end
end
```

This script creates an effect for a spell card that can only be activated if your opponent controls no "titan" monsters. When activated it allows you to add 1 "lightning" card from your deck to your hand. If you added "lightning-Maria" with this effect it also allows you to banish one facedown card your opponent controls. The effect of this card can only be activated once per turn.

Please note that you'll need to replace `0x123` and `0x456` with the actual setcodes for "titan" and "lightning" cards respectively. You'll also need to replace `10000000` with the actual card code for "lightning-Maria".