Jevil, Chaos Incarnate

Haste
Relentless (This creature may not be tapped, and must attack if able)
Imprison {u/r}: If you cast this card for its imprison cost, it becomes a legendary land, renamed
Kaard Castle Prison. When you tap it, you may add {u/r} to your mana pool.
To transform it back, pay {2}{u}{r}.