Alliance Training Center-5/Green Squad, also known by its shorter designation of ATC-5/GS, was a specialized training center for troops entering the Green Squad branch of the Rebel Alliance. It was located on the Outer Rim planet, Ksift, and was a 42 hour hike away from the closest city, Rakati. The only other Rebel facility on the planet, a security operation station, was a week's hike from the training center. The center was able to tutor 72 initiates at a time who were split into 8 training squads. Instructor Bret Hanson led the center and would be present at the final exam of each group. The ground floor of the facility held all the regular facilities for a training center, including a medical ward, weapons locker, communications, barracks and a kitchen whereas the second floor was kept a mystery to all initiates until the time of their final exam. They could only view it from the outside, where they could see it was a great dome which came to a full arc just under the tree line which was camouflaged and had tinted windows.
The second floor in fact contained the facilities for the final exam of each group. It was split into two distinct areas, a "forest" area, and a "Star Destroyer" area. Each area was designed to realistically recreate the landscapes. The lift into the forest area opened at the edge of a cliff which was five meters above a meter deep pond which was about ten meters wide. A forest began at the edge of this pond and beyond the trees was a building in a small clearing. The objective of this first area was for the group to simply get to the building, through the obstacles and past the simulation drones which were designed to shoot stun blasts at the groups. After clearing this area, the groups were allowed a short three minute break before going onto the second, Star Destroyer, area. The objective of this area was to retrieve a data file, Green3, from the computer systems. To do this, the groups had to get through a locked door and travel through the "Star Destroyer"'s hallways while defending themselves from drones and finally hack into the computer system and retrieve the file.
During one of these exams, with the group that would go on to become Green Squad 3, the Galactic Empire attacked this training facility. All initiates joined the fight in repelling the Imperials from the base, and eventually succeeded thanks to Green Squad 3 entering the Imperial's mobile command base and taking it out from the inside.