Clone Captain Rex served the
Rex has come to respect his Jedi General's unorthodox combat strategies and knack for daring improvisation. Rex has learned to think on his feet, and to never let seemingly overwhelming odds deter him.
Ahsoka holds the rank of commander in the Republic military. Rex at first did not know what to make of the overly eager youngster, but he now has come to greatly respect his Jedi commander.
Rex commands the 501st Battalion of clone troopers, serving under General Anakin Skywalker. The blue-emblazoned soldiers of the 501st have deservedly earned the reputation for getting the mission done.
Rex and Cody complemented each other's skills perfectly. Cody was procedure-minded, while Rex was far more impulsive -- attributes reflective of how each clone officer worked with their respective Jedi Masters, Obi-Wan Kenobi and Anakin Skywalker.
After being injured on a mission on Saleucami, Rex recovered at Cut Lawquane's farm. Rex disagreed with Cut's objections to the war, but respected the former trooper enough not to report his whereabouts to Republic command.