Drex, Eternal Pilot

Possess {2}{u/b}{b}{w/b}(If you cast this card for its possess cost, it's an Aura spell with enchant artifact. It becomes a creature again if it's not attached to an artifact. This ability costs {2} less when targeting an artifact creature.)
Enchanted artifact becomes a creature in addition with +X/X, where X is its mana
value.