- "What the..."
"Look, they're clones. We're all clones."
- ―This trooper and captain Rex.
Some time after the 501st Legion captured an Umbaran airbase, Jedi General Pong Krell informed the 212th Attack Battalion that the Umbarans had stolen clone armor and were preparing to attack. He then sent the clones to a location where they were supposedly hiding, to try and stop them.
The clone troopers of the 501st Legion, under the command of Captain Rex, also arrived at that location following a holographic message informing them that Umbarans had stolen their armor and weapons and have disguised themselves as clone troopers. When the two armies met, they began to attack each other, misled into thinking that the others were their enemies in disguise.
During the firefight, Captain Rex discovered that the opposite side were clones as well and ordered his men to stop firing and to take off their helmets. This trooper tried to shoot Rex, but Rex rushed into the open and tackled this clone trooper and removed his helmet, showing both sides the shocking truth. Rex then released the trooper who collapsed in tears.