Dig Through Death

Graveborn (You may exile any number of creature cards from your graveyard as you cast this spell. It costs {1} less to cast for each card exiled this way.)
Put the top seven cards of your library into your graveyard. Then, you may put up to two target creature cards from your graveyard onto the battlefield under your control. Those creatures gain haste. Exile them at the beginning of the next end step.