CS-227 was a First Order stormtrooper stationed on the Colossus platform on Castilon shortly before the Hosnian Cataclysm. He and two other stormtroopers were on duty in the station's control room after it had recently been sunk by Resistance personnel. CS-227 and his comrades determined that the station's reactors were, as had been previously reported, nonresponsive, making it difficult to raise the platform above the water again. When a Chelidae maintenance worker stopped outside the control room and waited in the hallway, CS-227 went out to force the worker to leave, only to be ambushed and knocked unconscious by Kazuda Xiono and Neeku Vozo. When CS-227's two fellow troopers went out to investigate, his unconscious body was thrown at his comrades as they were ambushed, allowing Xiono, Vozo and their allies access to the central control room. The Chelidae dragged away the bodies of CS-227 and his two fellow troopers.