A Delta Quadrant junk dealer who sold Voyager the derelict shuttle that Tom Paris named Alice.
Abaddon runs an alien junkyard where Voyager stops to trade for supplies in Alice. Tom Paris finds a derelict shuttle among his wares and persuades his superiors to bring it aboard for restoration, unaware of the influence it will come to have over him.
When Paris flees in the shuttle, Janeway contacts Abaddon and learns that he too has struggled with the craft's hold on him. From him the crew discovers that the intelligence inside the shuttle is trying to reach a particle fountain it considers home, which would destroy both the ship and its pilot.