A task of scouting was carried out by Jedi Knights Corran Horn and Ganner Rhysode in the year 25 ABY. Their objective was to locate and then investigate a missing xenoarchaeology research group from the planet Agamar which had stopped communicating with the university that had sent them to the planet Bimmiel. The Jedi got involved because it was suspected that the research team had encountered the Yuuzhan Vong from beyond the galaxy after their initial invasion via the planet Sernpidal.
Upon their arrival on Bimmiel, the Jedi determined that the team's communication satellite had sustained damage, which likely explained the loss of contact. This was further complicated by the planet's sun, which already made communication difficult. This discovery also strengthened the Jedi's suspicion that the Yuuzhan Vong had taken control of the planet, given their aversion to technology. After successfully finding the research team concealed within a cave, the Jedi learned that the team possessed the corpse of Yuuzhan Vong warrior Mongei Shai. When two members of the team were taken captive, the Jedi launched a rescue operation. During this operation, Horn killed the Yuuzhan Vong in charge of the camp, Neira and Dranae of Domain Shai, and was injured in the process. However, Rhysode saved him, going against orders in doing so. After learning that his grandfather's remains had been desecrated and his family murdered, Shedao Shai vowed to kill Horn. Shai's pursuit of revenge ultimately led to his death at Horn's hands during the Battle of Ithor and the subsequent destruction of that planet.
In 25 ABY, after the New Republic Senate ignored Leia Organa Solo's warnings about the invading Yuuzhan Vong in the Outer Rim, Jedi Master Luke Skywalker convened a meeting of the New Jedi Order on the moon Yavin 4. Following the meeting, he dispatched most of the Order on missions to gather information about the extra-galactic species. He tasked Jedi Knights Corran Horn and Ganner Rhysode with traveling to the planet Bimmiel to locate a missing Agamarian xenoarchaeology team, suspected to have encountered the Yuuzhan Vong. Rhysode was a member of Kyp Durron's faction within the New Jedi Order, which advocated for aggressive action against the Yuuzhan Vong. Horn, a staunch opponent of Durron's faction, caused Rhysode to reject the authority of the senior Jedi, perceiving him as weak. Rhysode was then attacked by garnants, released upon him by Horn's son Valin Horn.
Upon Horn and Rhysode's arrival aboard the Jedi shuttle Dalliance, they discovered that the xenoarchaeology team's communication satellite had been damaged. Continuing on foot through the desert in search of the team, the pair inadvertently entered a slashrat killing field, triggering an attack by the fierce and aggressive creatures. After repelling the slashrats, the Jedi sought refuge in a cave where the hostile xenoarchaeology team, led by Dr.Anki Pace, had been hiding. Meeting the team, they learned that certain sites on the planet had contained ancient Jedi artifacts, which had since been stolen. Rhysode, angered by the implication of Jedi involvement in the theft, joined Horn in convincing the team otherwise. Exploring further into the cave, Dr. Pace showed Horn a collection of unusual bones, which he immediately recognized as belonging to the Yuuzhan Vong.
Concerned that the Yuuzhan Vong had returned to the planet, possibly seeking the body of their advanced scout, Horn and Rhysode embarked on a scouting mission to confirm their suspicions. It quickly became apparent that their fears were justified. Discovering the Yuuzhan Vong's method of repelling slashrats, Horn collected samples of beetles found exclusively at the aliens' camp. The archaeology team examined the beetles, discovering that they released excessive carbon dioxide, disrupting the planet's delicate ecosystem. Horn proposed attracting slashrats to the camp using killscent and employing bio-engineered bacteria to neutralize the gas release, while using the Jedi's shuttle the Dalliance to extract them, but Dr. Pace rejected the plan, stating that they were academics and would not participate in combat. During their discussion, Horn and Rhysode realized that two students were missing from the camp. They were told that the students had gone to repair a meteorological station, but when Dr. Pace was unable to contact them, the two Jedi immediately set out to find them.
At the meteorological station, they found evidence of a struggle and a trail leading back to the Yuuzhan Vong base. They then spent several days observing the camp, watching as the Vong searched for the remains the team had found. They also discovered that, aside from slaves, there were only two Yuuzhan Vong warriors at the camp. Seeing the Jedi's plan as the only way to rescue her students Dr. Pace gave her team permission to proceed.
Rhysode and Horn infiltrated the Yuuzhan Vong camp to rescue the missing students, discovering that they had been tortured but not enslaved. They had been strapped to boards that kept them in constant pain. They then discovered that the boards release their grip when the person attached was in more pain, so Horn decided that the only way to get them out was to put himself in pain and transmit it through them. After the board released them, two Yuuzhan Vong warriors came back to the camp. Horn told Ganner to leave and take the students to the Dalliance despite him being wounded from the pain he inflicted through him on the students. He fought and easily killed the first warrior. Then, after a long fight with the second, Horn was bitten by the Vong's amphistaff but his enemy had been badly wounded and couldn't kill him. However, the venom slowly started to numb him, but he summoned a pack of slashrats and told them to eat the Yuuzhan Vong, then blacked out. Eventually, contrary to his orders, Ganner swung the Dalliance around, picked Corran up and put him in a bacta tank on board, saving his life.
This operation would significantly influence the immediate course of the war. Horn, who had presumed himself dead upon losing consciousness, awoke in a hospital on Coruscant several days later. Corran's reports of Jedi artifacts on Bimmiel prompted an investigation. Yuuzhan Vong Commander Shedao Shai also vowed to kill Corran Horn in retaliation for the deaths of his nephew and the desecration of his grandfather's remains. Shai's quest for vengeance culminated during the Battle of Ithor, where Horn killed him in single combat. Despite this victory and the Vong fleet's retreat, a Vong biotoxin devastated Ithor, wiping out its jungles. Horn would later feel guilt over this, holding himself accountable for the planet's devastation, leading to a temporary departure from the New Jedi Order.
Following the conquest of Bimmiel, the Vong fleet proceeded to attack worlds along the Veragi Trade Route: the next was Argazda which surrendered. The Yuuzhan Vong eventually met some New Republic forces in the Ciutric system which they defeated.
The Bimmiel mission first appeared in the novel The New Jedi Order: Dark Tide I: Onslaught, penned by Michael A. Stackpole. The mission was subsequently mentioned in Onslaught's sequel, The New Jedi Order: Dark Tide II: Ruin, also by Stackpole. Further mentions appeared in The Essential Atlas and The New Jedi Order Sourcebook. The Mission is also Ganner Rhysode's first appearance in Star Wars canon.