After Order 66 and the ultimate rise of the Empire Rex, Gregor and Wolffe wanting no part in the new order, still loyal to the now gone Republic and Jedi Order, made their way to Seelos eventually settling in an AT-TE which the 3 Clone Wars Veterans modified heavily over the years in order to catch Joopas and make their retirement more comfortable. That was until a Rebel cell came looking for assistance in finding a new base. The clones involvement with the rebels prompted the Empire to attack the AT-TE which suffered heavy damage and was ultimately unable to be repaired, leading to Gregor and Wolffe commandeering the sole surviving AT-AT later becoming known as Joopa Base after Rex left to join the rebels.