Hidden Cataract [Modern Horizons 3 Commander]

Set: Modern Horizons 3 Commander Type: Land — Cave Rarity: Common Hidden Cataract enters the battlefield tapped.T: Add U.4U, T, Sacrifice Hidden Cataract: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)