Thaarim, Potential Corporeal

First-strike, vigilance
Whenever you cast a spell from your hand with converted mana cost 3 or less, you may pay{g/u}{r/w}{u/b}. If you do, reveal the card third from the top of your library, if it has a converted mana cost 3 or less, exile the top two cards of your library, you may cast a spell or put a permanent into play from among the two if it shares a card type with the card revealed this way.