Sengir, The Progenitor

Flying
{3}: Regenerate Sengir, The Progenitor.
At the beginning of your endstep choose one --
Create X 1/1 white vampire token with lifelink, where X is the amount of damage you've delt to players this turn.
Create X 1/1 black vampire token with flying, where X is the amount of life you've gained this turn.