Grave Servitude
Mirage — common
Enchantment — Aura
Grave Servitude rulings:
2009-10-01: The sacrifice occurs only if you cast it using its own ability. If you cast it using some other effect (for instance, if it gained flash from Vedalken Orrery), then it won’t be sacrificed.
2004-10-04: The color change lasts only while this card is on the creature.