The Rebel Alliance had been retreating from the Mid Rim for 96 days before the campaign started. The Rebels lost many planets and had their forces retreating into the Outer Rim. The 61st Mobile Infantry, better known as Twilight Company, was sent in to provide cover for other battlegroups as well as to protect the Coyerti during their breeding season, where they were defenseless against Imperial bioweapons despite being hardy enough to defend themselves from them normally. Once the rebels secured Coyerti, it would aid in fortifying the territory between the Empire's control in the Mid Rim and the outer reaches of the galaxy.
Twilight sent in dropships with squads all along the planet. The squad led by Hazram Namir leaped right into the battle, attacking an Imperial camp. Gadren, who had charged right into the Imperial stormtroopers, escaped death only due to a faulty grenade that did not go off when it landed right at his feet. The attack went smoother after that, as Namir's squad coordinated with Sergeant Zab's squad in attacking an Imperial scout camp. The camp was freshly erected and was totally unprepared for the two squads. The squads attacked from different sides and overwhelmed the troopers in ten minutes. After that, they set charges and moved out quickly as TIE/sa bombers came to level the camp.
The next day, Namir and his squad had been trucking through a swamp for five hours when a message from Lieutenant Sairgon came through. The message said that the plans had been altered and a dozen rebel squads led by Carver would take the fort. Brand noted later in the day that they had destroyed it. Later, Namir woke up with a message saying to seek out and destroy an AT-ST. In total his squad had three grenades. Garden's first grenade missed, but the second one did visible damage to the legs. While trying to climb into the cockpit, Brand sprained her ankle falling. Namir and his squad eventually submerged the AT-ST in a swamp after attacking it all day.
On the fourth day, Captain Micha Evon decided to test former Governor Everi Chalis' information. Namir's squad was sent in to destroy an Imperial bio-weapon facility known as the Distillery, which would set back the Empire years on Coyerti. His squad marched all day to the facility and infiltrated it the next. Brand set a small explosive on a blue crate which set off an alarm. All of the staff exited the bunker and the team went in, with one of Twilight's newest recruits, Roach, shooting one man as they planted explosives. Thirty minutes later, with the squad safely away, the bombs went off and destroyed the Distillery. The team walked to the evacuation zone, during which they discovered they had been exposed to some bioweapon. Garden seemed to be immune and set up camp near the evacuation zone while the others. The dropship was not there and they had to wait a few days for it to come. Then, they were treated by the medics aboard the Thunderstrike.
Meanwhile, other Twilight forces led by Ajax were pinned down by a walker, with their air support, namely several X-wing starfighters, unable to get a clear shot. However, a drumming sound started and a massive army of Coyerti arrived. The Imperial lieutenant in charge surrendered and the rebels celebrated their victory.
The Coyerti campaign was not the only rearguard the rebels had that week. Several battle groups had all attacked Imperial worlds to allow the Alliance Fleet to evacuate from the Mid Rim. Other battles involved the 21st on Bestine IV and Bitter Pill Company, a group that lost its troop transport during their battle. Coyerti was one of the Alliance's only victories in the final Mid Rim Retreat. Losses included battles at Hope Station, Unroola Dawn, and Talrezan Four.
The Coyerti campaign appeared in the 2015 novel Battlefront: Twilight Company, written by Alexander Freed.