Steps of Shadow

Whenever a creature enters the battlefield under
an opponents control, Sacrifice it unless any
player pays {2} if the creature was not sacrificed in
this way,exile it instead unless any opponent pays
3 life, if the creature was not exiled in this way,
gain control of that creature at the beginning of
your next upkeep until end of turn. At the
beginning of your upkeep pay 3 life.
{t}: You may cast cards exiled with Steps of
Shadow without paying their mana costs.