Shul Alsyfa, the Abyssal Blade

Damage and life gained from white or red spells and abilities are halved rounded up.
Equipped creature gets +1/+1 and "whenever this creature deals damage to an opponent, you may cast target spell that player owns in exile. You may pay {b} and 1 life as if it was of any color to cast that
spell."
Equip: Sacrifice a creature or an artifact.