Unquenchable Thirst 
Enchantment — Aura
Enchant creature When this Aura enters, if you control a Desert or there is a Desert card in your graveyard, tap enchanted creature. Enchanted creature doesn't untap during its controller's untap step.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL