Burning-Tree Shaman

Creature - Centaur Shaman 3/4, 1RG (3)
Whenever a player activates an ability that isn't a mana ability, Burning-Tree Shaman deals 1 damage to that player.¹
Gruul shamans are bent on punishing the civilized. Any act more complex than rubbing sticks together or eating with utensils is met with the stinging burn of their magic.
Illus. Dan Scott

Gatherer Card Rulings [Nov 2009]

• 2/1/2006: A mana ability is an ability that adds mana to your mana pool, not one that costs mana to activate.

Format Legality	Legal in Vintage, Legacy, Extended, MTGO Classic Banned in Standard
Printings (1/9)	Guildpact (Rare)