|“||I was in the pilot seat, remoting a UH -- I was just dealing with some heat shields and... that's my last clear memory.||”|
— Carl Semken, recalling his last memory.[src]
In April 2103, Upsilon was evacuated and its staff was transferred to Theta. Carl Semken and his colleague, Amy Azzaro, remained to set up the Upsilon facility in a way that would keep its thermal plant running and to secure the power production for the entirety of PATHOS-II while the staff was absent by sealing blocks to prevent Mockingbirds from breaking anything.
On May 4, 2103, while Semken and Azzaro were close to finishing their task, Semken was attacked and killed by a Universal Helper robot.
While Simon Jarrett explores Upsilon, he finds a damaged Mockingbird containing Carl Semken's brain scan. The robotic unit believes itself to be a wounded human and begs Simon to call for help. When Simon confronts Semken about his current condition, he reacts in a surprised manner, angrily denying his current state.
Simon later discovers that he will need to divert power to the communications center in order to access it. To do so, he can pull the nearby lever, diverting power to the communications center, but also causing Semken extreme pain, evidenced by the auxiliary power tube that passes over Semken's broken mockingbird.
Alternatively Simon can disable the reactor flow in the far room. Doing so will redirect power, shutting down Semken's Mockingbird model in the process, effectively killing him. The resulting explosion will also attract the attention of a Construct to the area.