USS Onyx
USS Onyx (NCC-87356) was a United Federation of Planets vessel in service in 2413. The ship had participated in the Federation Civil War as a loyalist vessel, but served with distinction and honor. She was a vessel of the Steamrunner Class.
In 2413, the Onyx was dispatched on a diplomatic mission by the Federation Diplomatic Corps to aid in the transport of a Nertalli peace delegation to discuss a peace treaty with the Perthalla, with whom they had been at war for the last 75 solar years.
During their mission, however the Onyx went missing and Starfleet Command assigned the USS Hades, then studying the Magnetar PX 1354 nearby, to investigate that ship's disappearance.
After two days at warp, the Hades discovered the Onyx adrift and unoccupied, although it had appeared that the ship's crew had simply abandoned her. In the tradition of the Mary Celeste, the starship showed no signs of violence. There were no traces of the ship's crew.
The only truly bizarre thing about the Onyx was the fact that her Warp drive and other power systems were completely dead. There was no indication how this had happened, but even that event could not explain the disappearance of her crew and passengers.
More to come.
The USS Onyx was first seen in the USS Hades mission: Sphere of Terror