Darth Vader, Emperor's Will

First strike, haste
Wither
Whenever Darth Vader attacks, untap target creature. That creature blocks this turn if able.
Whenever a creature an opponent controls
with a -1/-1 counter on it dies during your
turn, untap Darth Vader. After this phase, there is an additional combat phase followed by an additional main phase. This ability triggers only once each turn.