Necromancer Initiate

{t}: Add {b}. Spend this mana only to cast a spell or activate an abilitiy that targets one or
more cards in a graveyard. Then, put a -1/-1 counter on Necromancer Initiate.
Whenever a creature enters the battlefield under your control from a graveyard, you
may remove all -1/-1 counters from Necromancer Initiate.