Mana Skimmer 
Creature — Leech
Flying Whenever this creature deals damage to a player, tap target land that player controls. That land doesn't untap during its controller's next untap step.
Legality
standardNOT LEGALpioneerNOT LEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL