Clarisse, Stealer of Secrets

Clarisse, Stealer of Secrets, can't be blocked.
Whenever Clarisse, Stealer of Secrets, deals
combat damage to a player, if you control five
or more permanents you don't own, you win
the game. Otherwise, that player reveals
their hand. You choose a card from among
them and exile it. For as long as it remains
exiled, you may cast it, and you may use mana
as though it were mana of any colour to do so.