Rona, Herald of Invasion

Whenever you cast a legendary spell, untap Rona. {T}: Draw a card, then discard a card. {5}{B/P}: Transform Rona. Activate only as a sorcery. ({B/P} can be paid with either {B} or 2 life.)

Trample Whenever a source deals damage to Rona, that source's controller exiles a card from their hand at random. If it's a land card, you may put it onto the battlefield under your control. Otherwise, you may cast it without paying its mana cost.