Frieren, the Slayer

Flying
Whenever Frieren attacks while there are three or more instants and or sorceries in your graveyard,
you may exile an instant or sorcery at random
from your graveyard to do one of the following effects:
- Cast a random instant or sorcery exiled with Frieren
without paying its mana cost, if you do put it into your graveyard as it resolves. Activate only if you own at least
2 cards in exile.
- Destroy target tapped nonland permanent.