Odessen

Located in the Wild Space, Odessen was a remote world, completely unsettled during the early Inter-Sith Wars period. Over 50% of its surface was covered in oceans and seas, while the terrain had healthy vegetation, with tall forests growing on the slopes of mountain ranges. The only known native species of Odessen were the shade stalkers, a predatory pack hunting species. Odessen was a Force nexus, and several Force-sensitives noted its strong presence in the Force, which was not attuned to either dark or the light side. Odessen's strength in the Force led to rapid escalation of evolution cycles in both native and introduced species.

The shade stalkers had thick scaly hides, indicating that they were not always a predatorial species, and did not seem to consume anything at all, puzzling the researches into how the creatures even survived. The jurgoran of Dromund Kaas were brought to Odessen at some point and evolved bioluminescent scales and a reflective hide to adapt to surroundings with little-to-no natural light, classified as a new cave jurgoran subspecies. More remarkably, when Doctor Juvard Illip Oggurobb introduced several new species on Odessen in 3631 BBY, he was able to observe significant evolutionary changes in less than a year. The sleen from Dromund Kaas showed a marked increase in agility and reaction time, makrin from Makeb altered their skin texture to match that of local forests, and Tarisian bogstalker evolved a plasteel-like barb on its tail-end, enough to classify them as the steel-tailed stalker.

Shortly after Galactic Republic's surrender to the Eternal Empire of Zakuul in 3636 BBY, Grand Master of the Jedi Order Satele Shan went into exile on Odessen, choosing the planet because of its unique Force properties. Landing her starship in the wilderness, the Jedi cleared a section of the forest with her lightsaber and established a small camp, in which she lived for several years with only the Force ghost of Darth Marr as her company. In 3631 BBY both of them have sensed the awakening of the Sith Emperor Valkorion in a new physical body, and began preparing for the arrival of the Commander, who unwittingly became Vitiate's latest host.

The Outlander was rescued from Zakuul by former Sith Intelligence Minister Lana Beniko, who began organizing a war against Zakuul and started looking for a location suitable for a permanent base. Odessen pulled at her through the Force, and after the Battle of Asylum served as a rallying cry for those who wished to oppose the Eternal Empire, Lana called her multiple contacts from the Sith Empire, the Galactic Republic and the criminal underworld to gather on Odessen. Lana and the Outlander arrived on Odessen onboard the Gravestone along with Senya Tirall, SCORPIO, T7-O1, Koth Vortena and his crew, which included Len Parvek, Ralo, and Tora. Lana's contacts were already waiting for them, and together they laid the foundations of an Alliance dedicated to oppose the tyranny of the Eternal Empire, of which the Outlander became the Commander.

Former criminals and law enforcement, soldiers of Empire and the Republic, and even the Sith and the Jedi worked together to construct the Alliance base on a cliffside, with extensive defenses above surface and expanded network of caves below. Large landing pads and docking stations were constructed for Alliance starships, including its flagship vessel Gravestone. Soon after the base was finished, it and the surrounding area were protected from an aerial bombardment by a planetary shield, ensuring that the Eternal Fleet could not wipe the Alliance out with a single devastating attack. The shield's construction was spearheaded by Doctor Oggurobb, and during the early stress tests it withstood the bombardment of Fleet Admiral Bey'wan Aygo strongest battleship.

The Alliance made several bold strikes against the Eternal Empire, which attracted new recruits and volunteers. When the Alliance planned an attack on the hyperwave relay station on Zakuul, Beniko suggested the Commander to contact Valkorion on how to best infiltrate the facility he had built. The Commander decided to do so in a secluded spot in Odessen wilderness, but Valkorion refused to part with any of his secrets. Valkorion announced that he lured the Commander into the wilderness so they could experience what it meant to face the death alone and overpowered his host pretending to leave their mind to attend to other matters, while knocking the Commander out cold. Satele Shan found their unconscious body and brought the Commander to her starship, which was still parked at her camp.

When the Commander awoke, the former Grand Master and the ghost of Darth Marr offered them insight on Emperor Arcann and his Knights of Zakuul, who possessed a different view of the Force from the Jedi or Sith. Following their instructions, the Commander collected items around the valley before venturing into a dark cave, where they proceeded to create a new weapon, infusing it with pure Force energy. At Satele's instruction, the Commander proceeded to a nearby oasis for their final trial, killing two young jurgorans, which angered their mother. After the Commander resolved the confrontation with her, Marr and Satele announced that they were leaving Odessen, having experienced a call from the Force, and the Commander returned to Alliance base.

During an attempt to take over the Eternal Fleet, SCORPIO betrayed the Alliance and took control of the Eternal Throne herself. She left a significant detachment of the Eternal Fleet seemingly under Arcann's control and manipulated her enemies to destroy each other by revealing Odessen's location to Arcann, while also warning the Alliance about his imminent arrival. As the Eternal Fleet led by Arcann's Eternal Flagship jumped in-system, the Alliance leadership boarded the Gravestone and faced them in orbit in the Battle of Odessen. Lana determined that the only way to ensure safety of the Alliance was to annihilate the Eternal Flagship and along with Senya Tirall accompanied the Alliance Commander in the infiltrating it. Senya separated from the others to find her daughter Vaylin, while Lana and the Commander went to confront Arcann on the bridge, when they learned that the Eternal Fleet had turned on Arcann and was now targeting the flagship to eliminate both him and the Commander in one fell swoop.

After reaching the bridge, Beniko stayed behind to deal with a squad of Zakuulan Knights, leaving the Commander to confront Arcann alone. The Commander defeated Arcann and crushed him under a pile of rubble, and as the flagship was coming apart, Beniko and her team commandeered a Zakuulan shuttle while the Commander narrowly escaped in a Zakuulan starfighter. On their way back to the Gravestone, Senya contacted them and revealed that she was with Arcann aboard his personal shuttle, taking her son into hyperspace to redeem him. Theron Shan then fired the omnicannon on the Eternal Flagship, creating a massive explosion that wiped out the present portion of the Eternal Fleet and winning the battle for the Alliance. The Battle of Odessen had become the rallying point the Alliance needed, swelling their ranks and giving them the capability to repel future invasions.

At some point the Shroud, a notorious criminal mastermind, infiltrated the Alliance base and planted bombs throughout it, but was stopped by the bodyguard droid HK-55 before he could detonate them and cause any damage. When the Alliance Commander went missing and was presumed dead on Dromund Kaas, former Republic Supreme Chancellor Leontyne Saresh arrived on Odessen in an attempt to take the Alliance over for herself. Saresh was making a speech in front of Alliance personnel when she was interrupted by the return of the Commander, who had survived the attempt on their life ordered by her. The former Chancellor tried to escape, but Lana cut her off, allowing the Commander to decide whether to imprison or dispose of the Twi'lek.

In Arcann's absence his sister Vaylin became the new Empress of Zakuul, and after breaking her mental conditioning on Nathema, launched another assault on Odessen, intending to finish the Alliance for good. The attack came when the Gravestone was caught in the dry dock where the upgrades from Iokath were being installed, and the Alliance fleet met the Eternal Fleet in Odessen's orbit, but without the Gravestone was unable to prevent Zakuulan ground forces from landing. The Eternal Empire sent a massive number of troops and ground vehicles to Odessen's surface, with World thrashers clearing landing spots in Odessen wilderness, Zakuul Hovercrafts deploying battalions of troops, and Eternal Empire Walkers providing heavy firepower.

Zakuulan troops focused on taking the Gravestone, but the crew sealed all entrances and frantically worked on finishing the upgrades to get the ship airborne. Heavy fighting broke around the Alliance base, with former Republic and Imperial soldiers fighting side by side against the Eternal Empire forces. Qyzen Fess led the Trandoshan Warstalkers, while Torian Cadera joined a group of Mandalorians to reinforce Bey'wan Aygo's position. Voss Mystic Sana-Rae and her students attempted to defend the Gravestone, but were forced to retreat when the enemy deployed heavy artillery around it. Vette volunteered to take care of the artillery guns with a rocket launcher provided to her by Doctor Oggurobb, who himself was busy securing the research inside his base.

The Alliance Commander, Theron Shan, and Lana Beniko returned from their mission to Nathema when the battle was already underway, and Theron dropped Lana and the Commander not far from the base and went to sneak behind the enemy lines and wreak havoc there. The Commander and Lana commandeered a walker from Vaylin's forces to clear themselves a path to the Gravestone, where the enemy troops started cutting their way through the ship's hull, but the crew finished installing the upgrades just in time and took off into space to face the Eternal Fleet. The Commander decided to lure Vaylin down to the surface of Odessen and used a holocomm to taunt her into a face-to-face confrontation. By this point, Torian was the only one left from this unit, cut off by an enemy ambush that threatened to overrun his position, while Vaylin's forces have pinned down Vette on another end of the battlefield.

The Commander made a tough decision to save one of their allies first, reaching their position just in time to clear off enemy forces that surrounded them. The Commander then rushed to aid the other combatant, but Vaylin had gotten to them first, taking her victim prisoner and sending the Commander coordinates for a direct confrontation on the Alliance landing platform. The Commander rushed back to the Alliance base, where Oggurobb's position was being overrun while Gault Rennow and Bowdaar had barricaded themselves inside the Alliance headquarters. The southern perimeter of Aygo's defense had been breached by enemy forces, who also pushed back Sana-Rae and her students, requiring Aygo to send reinforcements their way. Vaylin was waiting for the Commander with a host of skytroopers and Horizon Guards at her side, and the prisoner at her mercy. After Valkorion appeared in front of his daughter, calling Vaylin not worthy of the Eternal Throne, she responded by throwing her hostage at the Commander in a gesture of contempt, while reaching out with the Force to snap her victim's neck.

The Commander engaged Vaylin and bested her in combat, but Vaylin unleashed a massive Force Storm, threatening to bring down the entire Alliance base, and the Commander was forced to strike her down. With their will to fight gone, the Eternal Empire soldiers began surrendering by the thousands, while the Eternal Fleet retreated. The Alliance then traveled to Zakuul and claimed the Eternal Throne, gaining control over the Eternal Fleet, and establishing control over what remained of the Zakuulan military. It reorganized itself into the new Eternal Alliance, which continued to operate from Odessen even after growing from a small insurrection to one of the major galactic powers. The Eternal Alliance had relocated the Eternal Throne from the Spire of Zakuul to Odessen, where it was installed in the Alliance base, issuing the new orders directly to the Eternal Fleet.

Odessen first appears in Knights of the Fallen Empire Chapter IX: The Alliance, where it becomes the site of the player's Alliance new headquarters, which appears in almost every subsequent story update. Unlike most of the planets in the game, Odessen is not open to exploration outside the Alliance base, and most of the events on the planet take place inside instanced areas rather than in open world. Odessen also serves as a hub for gameplay activities, containing Galactic Trade Network terminals, Priority Mission consoles and entrances to several flashpoints. An "Odessen Proving Grounds" warzone was also added as a player-versus-player map.

At the end of the Objective Meridian flashpoint of the Onslaught expansion, depending on which faction the player sided with, the player is given the option to bring Odessen into the Galactic Republic or the Sith Empire or keep it independent; for those who side with the Republic, Odessen would gain its own Senator.