Tolarian Merfolk

Tether 1 (Whenever a permanent is exiled or phases
out, you may pay {1} and 1 life to exile 1 target
non-land permanent and return it to play under its
owner's control at the end of that player's next turn.)
Cannot attack unless defending player controls
an artifact.
"The sea, once it casts its spell, holds one in its net
of wonder forever." - Jacques Yves Cousteau