Necromancy

You may cast Necromancy as though it had
flash. If you do, its controller sacrifices it
at the beginning of the next cleanup step.

When Necromancy enters, it becomes an aura
with “enchant creature put onto the battlefield
with Necromancy.” Put target creature card form
a graveyard onto the battlefield under your control, attach Necromancy to it.
When Necromancy leaves the battlefield,
that creature’s controller sacrifices it.