You may cast Necromancy as though it had flash. If you cast it any time a sorcery couldn't have been cast, the controller of the permanent it becomes sacrifices it at the beginning of the next cleanup step.
When Necromancy enters, if it's on the battlefield, it becomes an Aura with "enchant creature put onto the battlefield with Necromancy." Put target creature card from a graveyard onto the battlefield under your control and attach Necromancy to it. When Necromancy leaves the battlefield, that creature's controller sacrifices it.
You may choose to play Necromancy as an instant; if you do, bury it at end of turn.
When you play Necromancy, choose target creature card in any graveyard. When Necromancy comes into play, put that creature into play as though it were just played and Necromancy becomes a creature enchantment that targets the creature. If Necromancy leaves play, bury the creature.
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