|“||Tau is a modular research platform for studying deep sea life, and human life, in extreme conditions.||”|
Site Tau is one of eight abandoned complexes featured in SOMA. It is here where the ARK is located, having been transferred here en-route to Phi, where the Omega Space Gun is situated. Several examination rooms, as well as staff quarters, can also be found here.
On September 13, 2103, Tau's evacuation towards Omicron was ordered, but its staff failed to reach the Climber due to being surrounded by marine creatures that work under the WAU's influence as a result of mutation by Structure Gel ingestion. The station and its staff soon lost radio contact with Omicron. Many employees were killed during the failed evacuation attempt, save for Johan Ross, Steve Glasser, Neil Tsiolkovsky, Antjie Coetzee and Auclair, who all remained stranded at Tau.
At some point after Tau's failed evacuation, Antjie Coetzee apparently ran to the observation sub-station near Tau to check on rations, though, as noted by Johan Ross, it was more like a failed suicide attempt. After that, as described in Item #4540, she climbed the Omega Space Gun's barrel in order to reach platform Omega.
On December 25, 2103, a party formed by Catherine Chun, Sarah Lindwall, Nicolai Ivashkin, Ian Pedersen, and Jesper Hill arrive in Site Tau, where they are joined by Neil Tsiolkovsky, and proceed to transport the ARK to Phi; along the way, Tsiolkovsky ends up dying in a landslide.
On December 27, 2103, after the ARK team has returned from Phi following their decision to postpone the launching of the ARK, opting instead to remain in Tau, Ross and Glasser decide to take the Climber that was originally scheduled to pick up the ARK group in order to warn Omicron about the critical situation at Alpha; Glasser dies en-route to the Climber after being viciously ripped apart by a marine mutation (assumed to be an Anglerfish).
After crossing the Abyss, Simon Jarrett finds Tau station abandoned and wrecked, with heavy traces of structure gel covering large areas of the site. Opening a large vault door, he narrowly avoids being discovered by Jin Yoshida hiding behind the door. Keeping his head down, he manages to crawl his way to the next vault door down the hallway and evade the Proxy, ultimately finding himself within the Tau staff's quarters.
Opening the doors to the Infirmary and Johan's room, Simon manages to discover more about Johan and his observations, studies and concerns, as well as find the ARK under the guard of the last surviving human being, Sarah Lindwall, who is hooked to a life support machine, barely living. After conversing with her, she allows Simon to take the ARK to launch, with her final request being that he turn off her life support in order to keep from living in solitude; Simon has the choice of whether or not to fulfill her request.
Simon transports the ARK in a cargo hatch leading to a separate Dive Room, where he is able to hook it onto a cargo transport system leading to Phi. While trying to activate the airlock system, it fails to equalize the pressure levels; Simon breaks the gushing pipes, allowing the room to flood before opening to the cargo tunnel. Simon follows the ARK through the tunnel before hitting a blockage caused by a tunnel collapse. He retraces his steps, attempting to find an alternate route, when Ross suddenly materializes in front of him, directing him to a dug-out tunnel leading through to a small cave system. Traversing the caves, he eventually stumbles upon the lost Alpha, overgrown with WAU intelligence.