Morrigan, Daughter of Corvus

At the beginning of your upkeep create
three 1/1 black skeleton creature tokens,
they gain haste. Sacrifice them at the beginning off the next end step.
{b}{b}{b}, {t}, Pay 7 life, discard your hand, sacrifice all artifacts you control: Return target face up creature card you own from exile or your graveyard to the battlefield tapped.