Rex's fate has not been revealed yet, so no one knows whether or not he was in Order 66 or if he wasn't even alive at that time.
Update: Rex was under the command of Skywalker and we all know who he became so Rex wouldn't have to do it since Skywalker Served the emperor palpatine
Well, he either died before Order 66, died during Order 66, or became a Stormtrooper. I don't really know for sure, for the final seasons of Star Wars the Clone Wars haven't come out yet.
Ahsoka's death is not yet cannon in the Star Wars universe. We know that she must die because of Order 66 but, how she dies has yet been decided or even when she dies. http://starwars.wikia.com/wiki/Ahsoka_Tano Well, when Rex doesn't exist in Episode 3 how so ahsoka my versions is : That Palpatine ordered to execute Order 66 and Rex's squad killed her and Anakin killed Rex. But I'm not sure and I hope that isn't right.
ANSWER 1NO!!! They they were always good, they just weren't the best when it came to having a bad leader. They are just as bad as the commander that orders them. Order 66 was if the Jedi went rouge.ANSWER 2Yup, the clones were just following orders from a bad leader, after all the clones were on the side of the ruling government.
Over half the masters and knights died because of order 66 and the clones
No. He escaped
Whether or not Rex was even around during Order 66 is still to be revealed
Rex's fate is still to be revealed
First of all, Ahsoka and Rex's fate are mysteries to be revealed. And if Ahsoka was around during Order 66 and Rex found her, she would be a traitor to him and every clone officer literally open-fired on their Jedi generals.
Rex retired The 501st over to Commander Appo and there is no record of Rex after that, Rex was long gone before order 66 occurred.
After Order 66, Rex and Cody, like so many other Clones, were merged into the Stormtrooper Corps.
Captain Rex obeyed order 66 then his chip that forced him to kill the jedi was removed by Ahsoka Tano in Star Wars The Clone Wars Season 7 2nd to last episode.
Well, he either died before Order 66, died during Order 66, or became a Stormtrooper. I don't really know for sure, for the final seasons of Star Wars the Clone Wars haven't come out yet.
68-66 years ago
Yes, the Tyrannosaurus Rex was from the order Suarishia
don't worry rex fan Rex is totally safe when the other clones turn bad Rex dose not instead he escapes killing the Jedi and flees to safety of naboo and joins the republic to fight against Darth Vader .don't worry he is still alive even after episode 6I think Rex died from saying no to chancellor palpatine to do order 66, sad thing by the way, or proubly frozed himself and told ashoka about it, so they frozed them self.
Ahsoka's death is not yet cannon in the Star Wars universe. We know that she must die because of Order 66 but, how she dies has yet been decided or even when she dies. http://starwars.wikia.com/wiki/Ahsoka_Tano Well, when Rex doesn't exist in Episode 3 how so ahsoka my versions is : That Palpatine ordered to execute Order 66 and Rex's squad killed her and Anakin killed Rex. But I'm not sure and I hope that isn't right.
No, it's believed Captain Rex was present throughout the Clone Wars, and presumably was alive during the rise of the Galactic Empire. He gives up his command of the 501st Legion to Commander Appo prior to Order 66.