Enigmatic Golem

When Enigmatic Golem enters the battlefield,
you may cast any number of instant and
sorcery cards with converted mana cost x
or less from your graveyard without paying
their mana costs. If an instant
or sorcery would be put into your graveyard
from anywhere, exile it instead.
Enigmatic Golem's power is equal to the
number of instant and sorcery cards you own in
exile.