Mystic Wastes
Land (Rare)

Tap: Search your library for a Island or Swamp card and put it onto the battlefield tapped. Shuffle your library, then put Mystic Wastes on top of it.

1U: Mystic Wastes becomes a 1/1 blue and black Cephalid Shapeshifter creature with flying until end of turn. It's still a land.

Justin Chan