Nikya of the Old Ways 
Legendary Creature — Centaur Druid
You can't cast noncreature spells. Whenever you tap a land for mana, add one mana of any type that land produced.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL