Ultimate Masters :: Creeping Tar Pit

Eratta

Land
Creeping Tar Pit enters the battlefield tapped. {T}: Add {U} or {B}. {1}{U}{B}: Creeping Tar Pit becomes a 3/2 blue and black Elemental creature until end of turn and can't be blocked this turn. It's still a land.

Other Releases

Worldwake
Ultimate Box Topper