Varkus the Blight

Delve (Each card you exile from your graveyard
while casting this spell pays for {1}.)
Whenever a creature would die, put two +1/+1 counters on Varkus the Blight.
Remove a +1/+1 counter from Varkus the Blight: target creature gets -1/-1 until end of turn.
{1}{b}: Sacrifice a creature and regenerate Varkus the Blight .
I don't live in darkness, darkness lives in me.