The Card Thief!!!

When The Card Thief!!! enters the battlefield make a money artifact token with {t} you gain {c}, and exile it with a sack counter on it. If a player would play a creature or artifact, make a copy of it under your control, and exile the card with a sack counter on it. The Card Thief!!!'s power and toughness are the number of cards exiled with a sack counter on it.