Yuriko, the Tiger's Shadow

Commander ninjutsu {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 mana value.