Black Hole

During ever players upkeep, they must choose
any card on the battlefield to sacrifice to the
Black Hole. Only cards that were on the
battlefield when Black Hole was played must
be sacrificed in time. It is suggested that you put
a counter or indicator on all cards that are on the battlefield when Black Hole is played. Sacrificed
cards are put under Black Hole and when all
cards are gone, exile all of said cards, including
Black Hole.