Kolin, Icy Operative

Tapped creatures opponents control have -1/-0.
Whenever a creature blocks or is blocked by
Kolin, Icy Operative, tap it. It doesn't untap
during its controller's next untap step.
Whenever Kolin, Icy Operative deals damage
to an opponent, choose a land that player
controls. That land doesn't untap during
its controller's next untap step.