Favor of the Opal Demon

At the beginning of your upkeep, sacrifice a creature. Put a creature from a graveyard onto the battlefield under your control, it has haste. Sacrifice it at the beginning of the next end step.
If you cannot sacrifice a creature, shuffle Favor of the Opal Demon into your library, you lose 5 life.
"You need only taste my power for yourselves, and I promise, you'll never taste anything like it again. "