Thran Turbine

Artifact, 1 (1)
At the beginning of your upkeep, you may add {1} or {2} to your mana pool. You can't spend this mana to cast spells.¹
When Urza asked the viashino what it did, they answered: "It hums."
Illus. Brian Snõddy

Gatherer Card Rulings [Nov 2009]

• 10/4/2004: The ability is optional. And you can add 0, 1, or 2 mana. You decide how much during resolution.

Format Legality	Legal in Vintage, Legacy Banned in Extended, Standard, MTGO Classic
Printings (1/6)	Urza's Saga (Uncommon)