Colonel Tobin was a male Human officer in the Onderon military until 3951 BBY when he joined General Vaklu in his attempt to wrest control of Onderon from then Queen Talia. Despite an alliance with the Sith Lord Darth Nihilus, the revolution failed. Tobin was spared from death and forced to serve aboard Nihilus' flagship the Ravager. During the Battle of Telos IV, Meetra Surik boarded the Ravager, intent on destroying the ship and its master. There, she found Tobin and convinced him to help in the destruction.
Before the Onderon Civil War in 3951 BBY, Tobin was the second in command of General Vaklu, who was the military leader of the Onderon military. Many Onderonians, including Tobin, believed that benefits with the planet's recent relationship with the Republic favored the interstellar government while Onderon's culture and resources faded. When Vaklu began to carry out his plan to overthrow his cousin and supporter of the Republic, Queen Talia, Tobin was responsible for provoking open conflict between Onderon and the Galactic Republic in order to instigate a civil war. At some point before the civil war broke out Sith Lord Darth Nihilus approached Vaklu, Tobin, and their supporters to offer his assistance in their endeavor.
Tobin was informed by an unknown source about the upcoming arrival of the Ebon Hawk. The Ebon Hawk eventually did appear near Onderon, as Meetra Surik planned to search the planet for Jedi Master Kavar. Tobin then ordered his fighter pilots to attack the vessel, which forced Surik to hide in the jungles of Dxun, the nearby moon of Onderon. This event triggered a space battle between the Republic fleet and Vaklu's fleet and, practically, the Onderon Civil War itself.
However, Tobin was not satisfied with the outcome, as he wanted to see the Ebon Hawk disintegrated. He reprimanded the captain who allowed the ship to escape and dispatched a group of scouts to Dxun to find Surik and her crew. Before the scouts could report anything, they were killed by Surik and the Mandalorian Kelborn.
When Surik, with the help of the Mandalorian leader Canderous Ordo, breached Onderon's military blockade and managed to contact Master Kavar in the cantina of Iziz, Tobin personally arrived with a squad of Vaklu soldiers, hoping to capture both Jedi at once. Suddenly, Kavar stunned all of Tobin's soldiers with the Force, and Tobin left the cantina to pursue Kavar, who had escaped.
Later, during the Second Battle of Onderon, Tobin commanded the strikeforce that infiltrated the Royal Palace, and while in the palace, killed a Twi'lek slicer named Kiph when he betrayed Vaklu and tried to escape. He used a drexl beast to disable the force field that guarded entrance to Queen Talia's throne room, planning to assassinate her. However, his plans were disrupted when the beast broke free of its handler, crushing everything in the hall, and incapacitated Tobin. Surik, who appeared in the palace just in time, left Tobin for dead while pursuing Vaklu and his soldiers to the throne room.
Colonel Tobin on board the Ravager, physically ravaged by Nihilus' dark presence.
Unlike Surik, Kreia realized that Tobin's injuries were not lethal. She decided to use him as a pawn in her own game against Darth Nihilus, the shadowy Sith Lord behind Vaklu and Tobin. She lied to the Colonel, telling him that many Jedi were hiding in Atris's secret academy on Telos IV. Tobin initially didn't believe her and fled the palace before the Royalist forces could capture him.
Eventually he found himself before Darth Nihilus and informed him of the academy. In his hunger for the Force, the Sith Lord summoned his fleet to Telos, which started the Battle of Telos. During it, Surik once again crossed paths with Tobin aboard the Ravager, Nihilus's flagship. By that time, Tobin had been physically ravaged by the dark side energy aboard the ship, likely a result of Nihilus's hunger, shown by his now gaunt appearance.
Tobin realized at last that Nihilus did not care for Onderon, and had he won the battle, it would be his next target. Still loyal to his homeworld, Tobin turned away from the Sith and agreed to help Surik and her Mandalorian allies destroy the ship, annoying Mandalore, who remarked, "We shouldn't waste our time with the weak," and promised Tobin that his men would shoot Tobin dead if the colonel were to "try anything stupid."
As an alternative to persuading Tobin to abandon the Sith (which works only if the player has high persuasive skills), the player has an option to kill him or not to engage in conversation with him at all, if the latter is chosen then Tobin would die in the explosion that destroys the Ravager.
Killing Tobin results in gaining "influence" with Mandalore while helping him "for Onderon" will result in an "influence" decrease, as described above.
Aboard the Ravager, Tobin's dialogue options are the same regardless of whether the player sided with the Royalists and Queen Talia or the secessionists and General Vaklu.
If Meetra Surik both speaks and acts supportively for General Vaklu prior to meeting Master Kavar in the cantina, then Tobin leading a team of soldiers in and attacking is not a real attempt to kill Surik again; it is a ruse. After Kavar flees back to the Royal Palace, Tobin shouts for the fighting to stop, and apologizes to Surik that "We have to maintain appearances." Attacking the Ebon Hawk when it first reached Onderon was not truly Tobin or Vaklu's choice; a Sith Lord they have allied with demanded they do it. Tobin explains the General is aware Surik has helped his cause, and that he wishes to break his current alliance with the Sith Lord and make a new one with Surik at the same time. If Surik accepts the offer, Tobin warns that for now Surik must leave Iziz and will be attacked on the way out by men loyal to Vaklu, so that the Sith "will be satisfied we are still loyal to them."
Instead of being called back to Dxun by Kelborn, Surik receives a message from Tobin and communicates with him directly before landing on Onderon again. When first greeting her, Tobin says, "It is good to see you", and details that "The war goes well, but victory is not yet certain." Displaying strategic and tactical ability, Tobin identifies two areas that must be dealt with for General Vaklu's forces to win the war: a Sith tomb on Dxun, and the Royal Palace on Onderon. He advises Surik that she will have to send a team to assault the tomb on Dxun while Surik herself- the Force-capable asset that Tobin and Vaklu need to break Talia's lines at the Royal Palace- returns to Iziz with one companion.
When Surik arrives, diving down from space in a Basilisk war droid, Tobin remarks with dismay that there are strong memories of the last time those machines came to Iziz, something Mandalore reacts proudly to. Surik leads a contingent of secessionist forces in storming the Sky Ramp and meets up with Tobin in the halls of the Royal Palace. Tobin stays in front of the main doors to the Throne Room, advising Surik and directing her from there. When the secessionist forces break through and assault into the Throne Room, Tobin is still taken down by the Drexl larva, and Surik still leaves him behind and proceeds into the Throne Room. Despite General Vaklu's victory in the Onderon Civil War in this version of events, Tobin still goes missing and, inexplicably given that he and Vaklu achieved their goals for Onderon, still appears aboard the "Ravager" late in the game.