Rona, Herald of Invasion - March of the Machine (MOM)

Whenever you cast a legendary spell, untap Rona, Herald of Invasion.
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.)
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Rona, Tolarian Obliterator
Trample
Whenever a source deals damage to Rona, Tolarian Obliterator, 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.