Cainhurst Summons

At the beginning of your upkeep, pay {r/w}
or sacrifice Cainhurst Summons. If you pay, exile a creature card from an opponent’s graveyard and put a Blood Counter on it.

When Cainhurst Summons is put into the graveyard, put a creature card exiled with it into your hand. It costs {x} red, white or neutral mana less to cast, where X is the
number of Blood Counters.