The black burner is a a tiny marine mammal, similar to a whale. It is 1-2 feet long, with a chubby, black body covered in soft skin, a puckered blowhole, and a wide, toothy mouth. They travel solitarily, or in schools of 3d4 members. They are unintelligent, and skittish (Unreliable (2) Morale).
Their main purpose is to serve as fuel for oil lamps and candles. They are covered in oil that prevents them from freezing when they emerge from the water to take abreath. The body of a black burner (they have an AC of 8 and 1-2 hp) can be lit, burning steadily for 3d4 hours. For easier transport, a cup of oil can be wrung from a black burner's corpse.