Assassin (This creature has flash. When it enters the battlefield, you may have it deal damage equal its power to target tapped creature you don't control.)
When Akali, the Rouge Assassin enters the battlefield, destroy target creature or planeswalker an opponent controls that was dealt damage this turn.
Akali can't block. Akali has hexproof as long as Akali is untapped.
"The words on their tombstones will be my new mantras."