Dimitri, Avenger of Faerghus

Commander Warp Staff {u}{b} ( {u}{b}, Return an unblocked attacker you control to hand: Put this card
onto the battlefield, from your hand or the command
zone tapped and attacking.)
Whenever a Ninja you control deals combat
damage to a player, reveal the top card of your
library and put that card into your hand. Each opponent loses life equal to that card's converted
mana cost.