Cartographic Balena

When Cartographic Balena enters the battlefield, return up to two other target creatures to their
owner's hands.
When Cartographic Balena leaves the battlefield,
Discover. (Look at the top card of your library. You
may cast it. If you don't, you may put it into your
graveyard.)
"They draw sea monsters only as map decorations."
—Captain Feira, eaten by a leviathan.