From Halopedia, the Halo wiki
A du'nak is a species of animal native to Rahnelo, a Sangheili frontier colony. A du'nak has two tusks and yellowed horns that spiral backwards. The animals have multiple trunks with whiskered jowls, and muscular back legs. Du'nak are protected from Rahnelo's cold climate by a coat of glossy black or mottled whitish-gray wool.
Du'nak are domesticated by the Sangheili of Rahnelo and used as beasts of burden. Some Sangheili also fashion cloaks spun from the wool of a du'nak. Gol 'Rhamee owned a du'nak, but both were killed in 2553 by Jiralhanae when Rahnelo was attacked by the Prelate Tem'Bhetek.
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