The merchant of the Trio, Onyx acts as the guard and haggler of goods that the Tough Love's group finds. While not particularly large for her age, she does grow in size with the more stuff they find. Originally she was one of the hatchlings belonging to a student from the princess's schools. Moonphase was the filly she was bonded with, the two leaving Luna's school just before the tragedy. Later the two were separated when Onyx wasn't allowed in the stable, and she has worn a locket with Moonphase's picture ever since. Having been socialized with ponies she became a traveling merchant as settlements began forming and eventually met Jet and Tough love.