Leviathan [The Dark] Angel then reveals the top card

then reveals the top card of their library

Set: Battle for Zendikar Promos Type: Creature — Human Scout Ally Rare Cost: {2}{W} Rally — Whenever Lantern Scout or another Ally enters the battlefield under your control

where X is the number of cards exiled this way

Set: Unstable Type: Artifact — Contraption Rare Cost: Whenever you crank Hypnotic Swirly Disc

Set: Fallen Empires Type: Creature — Dwarf Rare Cost: {R} {R}

Leviathan [The Dark] Angel then reveals the top cardSet: The Dark Type: Creature Leviathan Rare Cost: {5}{U}{U}{U}{U} Trample Leviathan enters the battlefield tapped and doesn't untap during your untap step. At the beginning of your upkeep, you may sacrifice two Islands. If you do, untap Leviathan. Leviathan can't attack unless you sacrifice two Islands. (This cost is paid as attackers are declared.)