Volkov, Bloodlord's Cavalier

Vigilance
Whenever two or more Vampire creatures you
control attack, put a 1/1 black Vampire creature
token onto the battlefield tapped and attacking.
Sacrifice a creature: Vampires you control get
+1/+0 until end of turn.
In a wave of black and grey, a steed and its rider
emerge. Clad in silver, red and white.