Veronica, Dissident Scribe

Menace

Whenever Veronica attacks, you may discard a card. If you do, draw a card.

Whenever you discard one or more nonland cards for the first time each turn, create a Junk token. (It's an artifact with "T, Sacrifice this token: Exile the top card of your library. You may play that card this turn. Activate only as a sorcery.")