The Spasm Plasm

As The Spasm Plasm enters the battlefield,
you may exile two creature cards from your
graveyard. If you do, The Spasm Plasm gains all
abilities and creature types of cards exiled this
way, except it is a 3/3 Ooze Horror in addition
to its other types.
Whenever The Spasm Plasm leaves the
battlefield, return all cards exiled with it into
their owner's graveyard.