Yuriko, The Tiger's Shadow

Commander ninjitsu {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 onto your hand
each opponent loses life equal to that card's
converted mana cost