Cheapest priced copy (Mirage): $0.35 at Card Kingdom, near mint, their price list as of .
Grave Servitude 
Enchantment — Aura · Common · Mirage · #126
You may cast this spell 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.
Enchant creature
Enchanted creature gets +3/-1 and is black.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
1 printing · $0.35 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Mirage | 126 | Common | $0.35 | — |
2 rulings from Wizards of the Coast
- 4 October 2004The color change lasts only while this card is on the creature.
- 8 December 2022The sacrifice occurs only if you cast it using its own ability. If you cast it using some other effect (for example, if another effect allowed you to cast it as though it had flash), then it won't be sacrificed.