With the Galactic Empire on the run, X2 and the rest of Grey Squadron set out to the planet Dathomir with the stated goal of investigating the Imperial prison on the world. Privately, however, X2—who was still growing acclimated to his ability to use the Force—acknowledged to his unit that his aim was to pursue his genetic brother X1, whom he sensed was involved in something untoward within the walls of the facility.
Grey Squadron was forced to infiltrate the prison by speeder bike through the dense foliage of the surrounding jungle. They were attacked by Imperial troopers on speeder bikes and were forced to drive through a rancor burial ground. On reaching the outer gates, X2 and Shara made a surprising discovery: a contingent of lightsaber-wielding Nightsisters fighting against both Grey Squadron and the stormtroopers within the outpost. Realizing the tactical advantage this presented, X2 and Shara split from the rest of Grey Squadron and pushed deeper into the grounds of the outpost. They quickly reunited with their allies at the entrance to the main building, at which point X2 began to sense something resonating powerfully with the dark side inside. Against Shara's wishes, he continued into the facility alone.
Within the bowels of the prison, X2 encountered the source of the disturbance: an enormous rancor being riden by the leader of the Nightsister assault. Calling on the Force for aid, X2 repeatedly used Force push on nearby rubble to knock the beast off balance, finishing it off with judicious use of his lightsaber. Once the rancor fell, the Nightsister Matriarch drew her lightsaber and attacked X2 on foot, but the Force-sensitive clone bested her in a duel.
The disturbance quelled, X2 and some of his squad members forged their way further into the prison's depths. After fending off several more Imperial ambushes, the group finally discovered X1's secret: a cloning facility, complete with cloning tanks filled with what appeared to be early-stage Wookiee clones. Unfortunately for Grey Squadron, X1 was not in the facility; however, X2 soon located his brother's private office in an adjoining room, and with Shara's assistance the unit was able to obtain a complete copy of his personal files.
The Star Destroyer explodes.
Upon returning to their ships, X2 and Shara were greeted by a grim sight: an Imperial saboteur had managed to slip detpacks into several of them, resulting in the destruction of numerous X-wings and the loss of many members of Grey Squadron. As X2 attempted to console one of the dying men, the remaining soldiers brought the captured Imperial before their distraught commander. Overcome with grief, X2 grasped the man with a Force choke and threatened his life, nearly giving in to his anger and falling to the Dark Side. Before he could do so, though, Shara interjected herself, reminding X2 that he must not follow his brother's path of vengeance. Chastened by his brush with the Dark Side, X2 let the humbled Imperial go, ordering his squadron to launch what ships were left and flee the planet.
In space, the survivors encountered an Imperial-class Star Destroyer. Unable to make their escape, X2 ordered the remnants of his squadron to attack the vessel, vowing never to run from the Imperials again. During the subsequent fight X2 successfully maneuvered his X-wing through numerous waves of TIE fighters, ultimately destroying the capital ship's bridge with several well-placed shots. The resulting explosion then detonated the rest of the Destroyer.
By mining the information gleaned from X1's personal data, X2 was able to discover the location of his brother's stronghold on the planet Mustafar. Though upset by the events on Dathomir, he vowed to find the resolve to finish the fight with his brother once and for all.