- "First squad, cover the retreat!"
- ―Captain Rex to first squad during the battle of Orto Plutonia
First squad was a squad of clone cold assault troopers that was part of a platoon of the 501st Legion and under the command of Clone Captain CT-7567 "Rex." First squad was among one of the units that fought in the battle of Orto Plutonia against Thi-Sen and his Talz warriors during the Clone Wars after Chairman Chi Cho of Pantora instigated a war between their forces and the Talz.
After failed negotiations between the two parties, the Chairman ordered Republic forces to follow him and mounted speeders. After being surrounded by the Talz and sustaining casualties, including the loss of the Pantoran guards and the Chairman sustaining a fatal injury, Clone Captain CT-7567 "Rex" ordered first squad to cover the retreat of Republic forces.
By the end of the battle, eleven clone troopers from the platoon were dead and the rest wounded, including Chairman Cho. After reinforcements arrived and a cease fire was in effect, Senator Riyo Chuchi was given permission by the Speaker of the Assembly to broker peace with the Talz after Chairman Cho's actions were called out of order, of which Chuchi was successful in accomplishing.