Necromancy

The reanimation spell that gives you the body but reserves the right to take it back, and the rules text buys two very different cards off a single payment. Cast it at sorcery speed and the creature is yours to keep, anchored to an Aura that sacrifices it only if the enchantment leaves. Use the built-in flash to drop it during an opponent's turn and the deal changes entirely: the next cleanup step arrives at the end of that same turn, so the creature is gone before you ever untap. The flash mode is not a free attacker; it is an instant-speed way to set up a leaves-the-battlefield trigger, dodge a sorcery-speed window, or pull a creature out of any graveyard for a surprise blocker that lasts one turn. The friction that balances the rate is that the body is never truly free; it lives and dies with the enchantment, so any disenchant, any bounce, any blink of the Aura takes the creature with it. That fragility is also the engine: sacrifice the enchantment to your own outlet and the creature dies as a leaves-the-battlefield trigger you can chain into death payoffs. Where blunter reanimation simply moves a card from graveyard to battlefield and walks away, this one stays attached as a leash, which is exactly what makes it the most interactive and the most abusable of the cheap reanimators.