Malignant Plaguecaster

Whenever Malignant Plaguecaster enters the battlefield or attacks mill two.
Whenever a nonland card is put into a graveyard
from anywhere you may pay {1} to exile it. If it
was a creature, gain one life and create 1/1 green
Pest token with flying.
{2}{u}{b/g}: Mill two, then return a nonland card of
an opponent's choice from your graveyard to
your hand.