Vael, Doomed Warden

Flying, vigilance, lifelink
Demons you control become Equipment artifacts
and are no longer creatures. They gain
"Equipped creature gets +X/+X, where X is this artifact's power. Whenever this card becomes unattached from a permanent, destroy that
permanent." and "Equip Angel {w}".
"Their power may be bound, but their whispers plague
me still." - Vael, Doomed Warden