Creeping Tar Pit - Borderless (EOS) from Edge of Eternities: Stellar Sights, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Calder Moore
• Card Text:
  This land enters tapped.
  T: Add U or B.
  1UB: Until end of turn, this land becomes a 3/2 blue and black Elemental creature. It's still a land. It can't be blocked this turn.