Devereaux, the Blue

skulk, Immortal (spells and abilities cannot reduce this creature's toughness less than 1.)
{w}{b}: Exile an artifact or enchantment you
control.
{u}{b}: Devereaux, the Blue gains +X/+X
and shadow until end of turn, where X is the
number of cards in exile you own. Shuffle a
random card you own from exile into your library.