Phenax, the Trustbreaker

Indestructible
As long as your devotion to blue and black is
less than seven, Phenax isn't a creature.
Whenever a card enters an opponent's graveyard
from anywhere, exile it instead.
{b}{u}, {t}: You may cast creature cards from your opponents' exile this turn, and you may spend
mana as though it was mana of any type to cast
those spells.