This expansion added the ground planet of Mustafar to the game, and was designed to capitalize on the DVD release of Star Wars: Episode III Revenge of the Sith and its final fight sequence between Darth Vader and Obi-Wan Kenobi, which was set on the same planet. Trials of Obi-Wan includes more than 50 new quests, from rescue missions to the exploration of a crashed Republic cruiser. Many quests also revolve around the return of HK-47 from Star Wars: Knights of the Old Republic, whom players can kill for a quest. The expansion also allows players to interact with the ghost of Obi-Wan Kenobi to help him "correct an imbalance in the Force" present on Mustafar. High-level quest rewards include the ability to find a fiery red crystal found only on the volcanic planet that creates a lava-like lightsaber. No new space sector was added with this expansion.
Trials of Obi-Wan is also available in the The Complete Online Adventures compilation pack.