The Crisis on Umbara unfolded in the wake of the War on Iokath. In an elaborate scheme to gain access to the Order of Zildrog, Theron Shan orchestrated a staged departure from the Eternal Alliance, deliberately setting a trap for his allies on Umbara. Theron, with the objective of securing a consignment of adegan crystals from an Umbaran hovertrain, intentionally released a communication using the same encoding techniques he had employed on Iokath, thereby drawing the attention of Alliance Intelligence. Accompanied by Lana Beniko and the Alliance Commander, he journeyed to Umbara and feigned a betrayal, confining his companions within the train cabin just before it collided with a mountain. Escaping before the impact, the pair pursued Theron on foot, but were unable to prevent his departure from the planet with a significant portion of the crystals. Subsequently, Theron Shan was fully integrated into the Order, while the Alliance initiated a search for his location.
Having gained knowledge of the Order of Zildrog, an organization aiming to dismantle the Eternal Alliance, Theron Shan, a key figure within the Alliance, contacted the Order's leader, Vinn Atrius, presenting himself as a potential recruit seeking the Alliance's downfall. Atrius initially dismissed him, prompting Shan to orchestrate a scheme targeting the Alliance Commander during the War on Iokath to demonstrate his loyalty. He then re-engaged with Atrius, who remained skeptical and requested that Shan acquire a shipment of adegan crystals from Umbara as proof of his intentions.
The crystals were being transported via a hovertrain en route to the Umbara capital city, under the protection of Umbaran soldiers and Shadow Assassins. Theron arranged for a communication from the train to be transmitted using the same encryption key he had utilized on Iokath, thereby alerting Alliance Intelligence to the supposed traitor's whereabouts. Upon receiving this intelligence, Lana Beniko promptly informed Theron Shan and the Commander, and the three embarked on a journey to Umbara aboard a shuttle to apprehend the "traitor".
Upon their arrival on Umbara, the team successfully boarded the train and confronted the Umbaran guards protecting the crystal shipment. They battled through the opposition, ultimately defeating Technician Canni and Shadow Assassin Elli-Vaa, eventually reaching the train's control room, only to find it unoccupied. Theron Shan then revealed his true allegiance, shocking his companions, and fired upon the Commander, inadvertently striking Lana instead. He then targeted the control panel, activating a force field that sealed Lana and the Commander within the cabin.
Theron then presented his fabricated rationale, claiming his desire for the Alliance's destruction since the demise of Valkorion and his intention to finally establish peace in the galaxy. After bidding farewell, Theron detonated several of the train's carriages, causing it to crash into a nearby mountain range, while he made his escape on a speeder bike. The Commander and Lana evacuated just before the collision and pursued him on foot, while also defending themselves against the local wildlife. With the support of the Umbarans, Theron managed to secure a significant portion of the adegan crystal shipment, loading it onto his shuttle. The Commander and Lana caught up to him, but were unable to prevent Theron's shuttle from departing Umbara and were forced to engage an Umbaran Spider Tank which was covering Theron's escape.
Following the defeat of the tank, Lana and the Commander returned to Odessen with the remaining adegan crystals. Lana informed the Commander that she was utilizing her spy network to locate Theron, as well as his mother Satele Shan. The Commander then decided to transmit a public holo message to Theron across the HoloNet. Impressed by his commitment to their cause, Atrius and the other members of the Order decided to welcome Theron Shan into the Order of Zildrog. Leveraging his unique infiltration abilities, he was tasked with locating a holomap containing the coordinates to Zildrog's location.
Depending on the player's decision to align with either the Sith Empire or the Galactic Republic during the War on Iokath, the Umbarans are joined by the opposing faction, now engaged in conflict against the Eternal Alliance to avenge the loss of their leader (either Jace Malcom or Darth Acina). Prior to the train crash, the player can address Theron in a peaceful manner, attempting to resolve the situation, or aggressively, vowing to pursue him; this choice will influence dialogue during the subsequent two flashpoints. In their HoloNet message to Theron following the mission, players can either pledge one hundred Eternal Fleet warships as a peacekeeping force under his command in a Light Side option, or denounce him as a terrorist and a madman, placing a one billion credit bounty on his head in a Dark Side option.