- "Your priority is to stop the UIR advance within Kashkur. COG forces hold the central plains of the country and the extreme west, but the UIR is widening its corridors between the areas we still hold. The Anvegad Pass is blocked and must remain so if we are to stop the UIR closing the circle and inserting land forces from the east."
- — Choi, giving orders to Lt. Victor Hoffman to hold Anvil Gate to slow the UIR advance
Commander on the Western Front of Kashkur
Briefing Captain Adam Fenix
- "They're running late, Fenix. I expected them to invade weeks ago."
- — Choi, on the UIR and the neutral nation of Vasgar
In 17 B.E., Choi arrived at Forward Operating Base Tyro in western Kashkur to brief Captain Adam Fenix of Howerd Company, 26th Royal Tyran infantry, on his mission to close down the border with Vasgar. As they went over maps of the region in a tent, Choi told Adam that he had expected the Union of Independent Republics to invade Vasgar weeks ago, and they wondered what was taking them so long to act. Adam asked him if they were going to assist Vasgar in defending itself from the UIR, but Choi told him since it was a neutral country, the Coalition of Ordered Governments was going to allow the UIR to tie up resources there, and that their job was to hold the western end of Kashkur, especially the city of Shavad, where the UIR would need to move armor through. As he finished the briefing, he asked Adam if Lt. Helena Stroud had told anyone who the father of her daughter was yet, but Adam told him she had not. He then informed Adam that before his company was deployed to Shavad, he needed to shut down several Imulsion pipeline hubs that went into Vasgar, in order to cut off vital supplies to the UIR. Adam was worried about well-being the civilians in the country, but Choi told him angry civilians would just give the UIR something else to worry about. Choi ordered Adam to have his forces in place by that night, and that he would contact him at twenty-five-hundred for an update. He then returned to the Brigade HQ in Lakar on his personal Tern.
Invasion of Kashkur
After the UIR invaded Kashkur, they attacked Shavad, and began the siege of Anvil Gate. Captain Ranald Sander, the commander of Anvil Gate, contacted Choi and asked for permission to take out an Imulsion refinery in the path of the besieging Indie forces, in order to deny the fuel there to the UIR. Choi denied him permission, due to the civilian population still at the refinery. After Sander was killed, Choi ordered his second-in-command, Lt. Victor Hoffman, to hold Anvil Gate no matter what in order to prevent the UIR from overrunning Kashkur. Hoffman later contacted him, and informed him that the UIR had cut off water to the city. However, Choi was unable to do anything to help him, since he needed the pass to Anvil Gate closed, and did not have the forces available to send reinforcements. Choi later appealed to Chief of the COG Defense Staff General Kennith Markham-Amory to send some kind of help to Anvil Gate, but Markham-Amory refused.
Battle of Ragani
- "Fenix was right. We should damn well pull back."
- — Choi, as the situation in Kashkur worsens
Choi was later forced by General Brode to send Adam and his company, which had fallen back from Shavad with half the company dead, to the city of Ragani, to stop a group of eight Indie armored vehicles, and keep the road open for the Andius Fusiliers Regiment. However, after they arrived, Adam contacted him and informed him that there were only four APCs. Choi then received an update from Intel, and that that had just been a scout group for at least twenty more vehicles, including tanks. Choi passed this on to Adam, and told him that he would keep him updated on any new information. Choi later met with Brode in the ops-room at Lakar, telling him that they should have committed air assets to assist Adam. Brode told him they didn't have any to spare, and Choi began to agree with Adam that they should fall back from Kashkur. Brode informed him the Chairman would not allow that, but they were interrupted when a comm officer informed them that the Fusiliers C.O. had contacted them and informed them that they had broken through and joined up with Adam. Choi asked how many casualties they had suffered, but was told there was no word. Brode commented on how talented but dissatisfied Adam was, and wondered if they should promote him. Choi didn't think ambition was what was driving Adam, and Brode commented on how he always seemed to think he knew better than command. Choi corrected him, believing that Adam thought it was himself who should be doing better, and could fix the whole war if he tried hard enough. Brode thought that Adam would be better suited in the Defense Research Agency designing weapons, but Choi doubted it would ever happen, since Adam would consider it a soft option to design weapons and abandon his men.
Commander on the Sarfuth-Maranday Border
Two months later, Choi was commanding the 26th RTI on the Sarfuth-Maranday border. When Intel came in that the UIR was going to attack Sarfuth from the Republic of Lauczi through the Maigar Pass, Choi made a plan to intercept them at the town of Reinne. However, Indie radar would detect insertion of forces via helicopter, forcing Choi to try and move his men into position on the ground. Major Baxter and Captain Hoffman came up with a plan to take out a radar station at Gralia in Lauczi, but had to cross the neutral Maranday border to do so. Hoffman and his team succeeded, but were forced to kill three Maranday border guards in the escape, causing the country to log a formal complaint. Choi was furious with Hoffman, but was able to use Terns and King Ravens to land his troops in Reinne.
- They Also Serve
- Gears of War: Unseen (Mentioned only)
- Gears of War: Anvil Gate (First appearance) (Appears in flashback(s))