Populace Cleanse

in your endstep add 3 charge counters to
Populace Cleanse.
{1}{b}: Remove 3 charge counters. when
Populace Cleanse enters the graveyard
trigger its sacrifice ability twice.
{3}{b}{b}, Sacrifice Populace Cleanse: create
one 5/5 black demon creature token with
flying. remaining charge counters are +X/+X