Kanshu, the Soul Cage

When Kanshu, the Soul Cage enters the
battlefield, exile up to one target creature an
opponent controls until Kanshu, the Soul Cage
leaves the battlefield.
Whenever Kanshu, the Soul Cage or equipped
creature attacks, it gets +X/+0, where X is the
exiled card's mana value.
Recofigure {2}{w}{w}