Undercity sewers

Located in close proximity to the Undercity on the planet Taris, the Undercity sewers acted as a central point for various sewage drains from the surrounding area. It was linked to other similar sewage facilities through a network of extended metal pipes. The majority of the complex was constructed from a material resembling permacrete, securely fastened with metal bolts, along with sizable, rusted metal sheets. The system, powered by continuously moving gear trains, transported waste into one of four large reservoirs. Droids were responsible for removing the waste, although by 3956 BBY, they were largely absent or malfunctioning.

The Undercity sewer complex included at least one maintenance level that, by 3956 BBY, was largely unmonitored. This resulted in the pipe system falling into severe disrepair, with untreated sewage flowing directly through several sections of the level. The pervasive stench of waste permeated the area, with an odor reminiscent of the planet Gamorr. The walls of the maintenance level featured simple, golden lines and circles in various locations and were illuminated by numerous dim lamps.

The sewer system on Taris was established sometime before the Tarisian Civil War, which occurred a century prior to the Jedi Civil War. Its purpose was to manage the sewage originating from the buildings surrounding the Undercity.

Somehow, the Rakghoul disease found its way into the Tarisian Undercity. As a result, the city was abandoned, and the sewer system was left to decay. Eventually, it was overrun by Rakghouls and Gamorrean slavers, yet it continued to serve as the planet's infrastructure.

Following the civil war that led to millions of civilian casualties, thousands of the poorer citizens of Taris who had rebelled were imprisoned. When the prisons reached capacity, the rebel prisoners were exiled to the Undercity, where they formed a group known as the Outcasts. Rukil, along with his father and grandfather, were among them. As the inhabitants of the Undercity began to believe in a "Promised Land," a mythical location on Taris said to be entirely self-sufficient, older generations of Rukil's family embarked on a lifelong quest to find a path to it. The two discovered a route to the depths of the sewers, where they ultimately met their demise, thus guarding the secret. Consequently, Rukil dedicated his life to searching for this mystical place, but without success.

By the time of the Jedi Civil War, the system's maintenance had completely ceased, causing it to become rusted and dysfunctional. Due to the lack of upkeep, criminal elements disabled the manual locks on the facility's maintenance levels, and it soon became a hideout for Gamorrean slavers. They utilized numerous small sections of the vacant complex as holding cells for captives. The Black Vulkars gang, based in the Lower City directly above the sewers, were compelled to establish a defense system consisting of a ray shield and mine grids to prevent elements from the Undercity from wandering through the sewers to their headquarters. At some point, a rancor entered one of the sewer's maintenance levels, settling in the northeast and surviving by consuming those who wandered into the sewer.

In 3956 BBY, the Sith Lord Darth Malak's Sith Empire took control of the planet, and patrols were dispatched into the sewers to search for surviving crew members of the destroyed Galactic Republic Hammerhead-class cruiser Endar Spire. Of particular interest to the Sith was the Jedi Knight Bastila Shan, a Human female capable of performing battle meditation. Several soldiers were killed by the sewer residents. At that time, Rukil, following in the footsteps of his father and grandfather, had grown too old to continue the quest of searching for the "Promised Land" and had instead sent his young apprentice Malya to continue his work.

Shortly afterward, Revan, the former Dark Lord of the Sith, entered the Undercity to rescue Shan from the Black Vulkars. He enlisted the help of Mission Vao, a teenage Twi'lek and local resident, to guide him through the sewers to the Black Vulkar headquarters. In exchange, Revan agreed to save her Wookiee companion, Zaalbar, from the Gamorrean slavers within the sewers. Before entering the sewers, Revan discovered the corpse of Malya, whose journal contained information leading towards the sewage complex.

Upon descending into the sewers, Revan and his companions eliminated several victims of the rakghoul plague, beings mutated into creatures known as rakghouls that had overrun the sewers, as well as Gamorreans, before ultimately rescuing the Wookiee. In return for his assistance, Vao deactivated the shield that was preventing Revan from accessing the Black Vulkars' lair from the sewers. As Revan and his friends fought their way through the sewers, they discovered remnants of Rukil's father and grandfather and collected their journals, which contained their findings. They later returned these journals to Rukil. Through the passage, Revan then encountered the rancor in the northeast of the complex but managed to overcome it to enter the base. After Bastila was eventually freed from the Vulkars, Malak ordered the Sith fleet to bombard the planet's surface to eliminate her, destroying the surface of the planet in which the rubble from the upper levels landed on the Undercity ground. This flattened large parts of the sewer system beneath, and most if not all of the remaining Gamorreans perished. This had ended the disorganized slavery in Taris's Undercity.

The Outcasts were able to descend from the Undercity into the sewers and navigate through what remained of the understructure during their months-long journey to the Promised Land. Having survived the bombardment, they did not encounter any other survivors of the bombardment in the sewers, Gamorreans or otherwise. Eventually, the Outcasts descended even further into Taris and reached the Promised Land.

During the Cold War, the Galactic Republic established a settlement on the ruins of Taris in the hope of rebuilding its city to demonstrate that the Sith Empire could be defeated. Much of the sewer system remained, and different sections were converted into various facilities. However, the Undercity was still overrun by Rakghouls, which had evolved to be more intelligent and use weapons, and a majority of them still lived in the sewers and would attack and infect travelers. Some of them had even evolved into Nekghouls but unlike the Rakghouls, the Nekghous couldn't spread infection. Governor Saresh struggled to stamp out corruption in the military and civilian forces across Taris. Thanks to her efforts and her dedication to the cause, the initiative was making more progress than it had in the last decade.

However, thanks to the assistance of various members of the Empire, Gravus succeeded in halting the project, and Taris, including the broken up sewers, were for an unknown period of time, consequently occupied by Imperial Forces.

By 3 ABY, much of Taris had been rebuilt, including the four cities above the planet's under structure, but it is unknown if the sewer system below had ever recovered.

The sewers served as a habitat for several criminal gangs and dangerous creatures. Notably, the Black Vulkars gang, led by Brejik, controlled both entrances to the upper sewers area. In addition, a group of Gamorrean slavers operated from the lower sewers, capturing passers-by and selling them to other criminal groups on the planet. The disappearance of individuals wandering the lower levels of Taris was unlikely to be noticed, which significantly reduced the risk of the underworld inhabitants being discovered by Tarisian security forces.

Some residents of the Undercity held a belief in the "Promised Land," a mythical location on Taris said to be entirely self-sufficient. This belief, coupled with the desire to escape the poverty of the lower levels, motivated at least three villagers to venture out in search of the fabled colony: Rukil's grandfather, father, and apprentice—Malya. All three discovered clues regarding the whereabouts of the Promised Land that led them towards the Undercity sewers, but they all perished within the complex.

Following the crash of the Endar Spire, several Sith soldiers were dispatched to the sewers, leading to overcrowding in the area. Multiple patrols were sent into the sewer complex to ensure that neither Bastila Shan nor any Republic soldiers managed to escape. At least some of the Sith soldiers involved were violently killed.

Victims of the rakghoul plague were excluded from the Undercity by a large metal wall, forcing them to seek food and shelter in the nearby sewer complex. They soon occupied large portions of the structure, posing a threat to its other inhabitants. Another danger to the public was a large rancor that managed to find its way into the sewers around 3956 BBY. It operated from a large hall just outside the sewer entrance to the Black Vulkars gang's base, severely restricting access to and from the hideout.

Although separated from the rest of the sewers by the aforementioned energy shield, the upper sewers contained several rakghouls and slavers. The area was effectively sealed off, with the only two entrances being the corridor from the lower sewers and the elevator up to the Black Vulkars' base. The upper sewers originally had an additional entry and exit with a single ladder leading upwards, but it was blocked off by 3956 BBY.

The maintenance level, referred to as the lower sewers, was heavily infested with criminals and animals, even more so than the upper sewers. Two ladders provided easy access to the level from the area directly surrounding the Undercity. Most functional doors in the area had manual locks that could be picked and bypassed. The level contained large groups of rakghouls while serving as the main base of the Gamorrean slavers. The Black Vulkars, fearing for their safety, established a ray shield and heavily mining the level to sectionalize the sewers and protect their territory.

The Undercity sewers are featured exclusively in the video game Star Wars: Knights of the Old Republic. Players are required to visit this area to progress in the game's main storyline. Mike Trottier, a level artist at BioWare, contributed to the design of the area.

In a non-canon dark-side ending, players have the option to not return to the Undercity and retain the "Promised Land" journals, or they can sell the journals to Igear in the Outcast village, who subsequently destroys them, preventing the discovery of the "Promised Land."

The Taris Undercity reappears in the roleplaying video game Star Wars: The Old Republic, where the remains of the city are among the locations visited, with the sewers being indirectly referenced.