WARNING: The following contains spoilers for the Star Wars: The Clone Wars series finale, streaming now on Disney+.
Until the surprising return of Star Wars: The Clone Wars for Season 7, fans did not know the show would offer them an explanation to fill in some of the gaps in the stories of their favorite characters, particularly Ahsoka Tano and Captain Rex. Popular both on the series and on its successor, Star Wars Rebels, there was a large gap in their history, and the best way to fill in the absence of a finale was the novel Ahsoka. Except now we have the TV finale fans always wanted, and it contradicts a few details from Ahsoka.
The 2016 novel, by E.K. Johnston, provided the few details audiences had until now about the former Jedi and her clone trooper companion's escape from Order 66. That both characters appeared on Rebels made it clear they survived, but the series itself never offered an explanation. When it comes to the story provided in the novel, there are some details that fit in with the finale and others contradicting it.
One of the biggest commonalities is the mission Ahsoka and Rex were on when Order 66 took place. In both the novel and the finale, they are overseeing the capture of Darth Maul, whose involvement in the Mandalorian conflict came to a head following the Sith Lord's own battle with Darth Sidious, who played all the pieces of the galaxy against each other. However, in the novel, both Ahsoka and Rex are still on Mandalore when Order 66 takes place. In the finale they are aboard a Star Destroyer initially bound for Coruscant that sets the stage for their epic escape.
The mechanism behind Rex's freedom is also a key difference between the two. The novel provided the context that Rex and his brothers-in-arms Wolfe and Gregor (also seen in Rebels) had their obedience chips removed following the incident with Fives. Fives was a clone trooper from earlier in The Clone Wars who almost blew the lid off the entire plot to enact Order 66, but Rex's discovery of the plot was downplayed in the actual finale and confined instead to a confidential report Ahsoka discovered. Most notably, his chip was not removed until after Palpatine gave Order 66.
That raises the question just how Wolfe and Gregor were able to escape the obedience chip's influence. While the novel's explanation satisfied the mystery, the retcon created by the finale presents a dangling question that may never be resolved in the canon. It could be possible Ahsoka and Rex set out to free other clones after the fact, but there just don't seem to be any definitive answers as of yet.
The differences between the novel and the finale do not end there, either. The circumstances of Ahsoka and Rex's "death" prove to be a point of difference between the two as well in subtler ways that may be easier to ignore. The novel depicted false graves Ahsoka and Rex left, with the former leaving a green lightsaber at the site of the grave and a trooper helmet hinting at Rex's own death. Homage was paid to the scene in the show's finale, but there were a few changes.
Ahsoka and Rex in the show do not construct actual graves, and the lightsaber Ahsoka leaves is, of course, one of the blue ones recently gifted to her by Anakin. The object ends up proving the focal point of the series' closing moments, as the now-transformed Darth Vader marches up to the site of the Star Destroyer's crash and uncovers the blue lightsaber that, in a simpler time not so long ago, he gifted to Ahsoka as a symbol of restoration and friendship.
The finale adds to the emotional resonance of the moment compared to the novel's depiction, playing up the relationship between Anakin and Ahsoka as the overarching heart of a show that was so broad in scope. But at the same time, the soft retcons to the canon indicate either an inattention to, or disregard for, the established facts of the Star Wars universe. The canon novels are supposed to matter precisely because they're canon, but if the events in those novels are discarded when a TV show or movie finds them inconvenient, then it cheapens the connectivity of the world of Star Wars as a whole.
Streaming on Disney+, the final season of Star Wars: The Clone Wars stars Matt Lanter as Anakin Skywalker, Ashley Eckstein as Ahsoka Tano, Dee Bradley Baker as Captain Rex and the clone troopers, James Arnold Taylor as Obi-Wan Kenobi, Katee Sackhoff as Bo-Katan and Sam Witwer as Maul.
