Lt. Selan is grateful to the Republic for liberating him from the Collective and treating him with respect, which is more than what a former employer, the Tal Shiar, has done for him. There, he was tasked with retrieving Borg technology until he was assimilated into the Collective during a botched mission. He was later liberated from the Collective by a Romulan Republic vessel and is slowly reintegrating himself into non-Collective life in the Republic.
- “Taris”: Selan joins Federation players in the Hobus System in a mission to discover the truth behind the destruction of the Romulan homeworld.
- “Republic Day”: Romulan Republic players visit the bridge of the Lleiset in orbit of New Romulus and meet with Gaius Selan and the rest of his crew.
- “A Step Between Stars”: Selan can be seen with the rest of the Lleiset's crew when they are being briefed on the mission.
- “Capture the Flag”: Selan requests the player's aid when the Lleiset is boarded by the Vaadwaur in the Orlitus System, and coordinates the effort to retake the ship. He also mentions that he has run hundreds of holodeck simulations of various hostile groups boarding the ship, including the player.
- “Uneasy Allies”: It is revealed that Empress Sela has the ability to control Selan through his Borg implants, and that she used him to escape from Republic custody. The player catches up with them in the Hobus System, where Sela agrees to release Selan. He is beamed to the player's ship to recover.
- “Butterfly”: In Scenario Gamma, one of several holodeck simulations designed to test the use of the K.I.S. Annorax against various targets, Gaius Selan is a Tal Shiar officer stationed aboard the I.R.W. D'serek. Temer and the player arrest him after deciding to defect to the fledgeling Republic.
- “Midnight”: Gaius is aboard the Kyana Research Station prior to the briefing on the Iconian Resistance's final battle.
- In Tales of the War #10, it is revealed that since the events of “Uneasy Allies”, Selan has been spending his spare time searching for Sela. Doctor Rhian Cratak offers him comfort, and encourages him to abandon his search, arguing that wounds will not heal if one keeps opening them.