Belzarond, Void's Rage

Haste, flying.
Whenever Belzarond, Void's Rage attacks, it
deals X damage to any target, where X is equal to
the number of Demons you control.
Partner with any number of different Belzarond
(When this creature enters the battlefield, target
player may put any number of different creatures
named Belzarond into their hand from their library,
then shuffle.)