Niner's squad was a group of clone commandos who served in the Galactic Republic's Grand Army from 32 BBY to 22 BBY. Cloned on the Wild Space planet Kamino in 32 BBY, the squad was led by Niner, and consisted of clone commandos Two-Eight, O-Four, DD, and Sev. During the commandos' training under Cuy'val Dar training Sergeant Kal Skirata on Kamino, 28 was killed due to an explosives error of his own doing on a live-range exercise—an event that would weigh heavily on the squad leader. The squad received either O-Four, DD, or Sev as a replacement in 28's stead, but Niner observed that the new trooper seemed to feel as if he was not accepted by the unit. In 22 BBY the squad was deployed to the Outer Rim world of Geonosis in the first battle of the Clone Wars. In the battle, three of the squad's members were killed in action, leaving Niner as the only survivor to be assigned to Omega Squad shortly after, which he remained as squad leader for the duration of the war.
RC-1309's squad was mentioned in the 2004 novel Republic Commando: Hard Contact, written by Karen Traviss. In a 2005 discussion forum on StarWars.com, Traviss stated that RC-1309's original squad was named "Lambda Squad" in her notes for Hard Contact, but the name did not appear in the novel itself.