Star Wars: The Clone Wars season 7 may have made a legendary Mace Windu scene canon. The moment in question comes from the 2003 Genndy Tartakovsky Clone Wars cartoon. The original series was over-the-top as Jedi were akin to superheroes more than they already are. The battles were big, and the presentation was unique. It was a stark departure from the events of the clone war depicted in the prequel films. Thanks to the 3D animated version of the series beginning in 2008, the 2D one was made non-canon. However, a classic fight scene involving Mace Windu may be a part of the new Clone Wars' history.
In the original scene, Windu and a handful of clones are on Dantooine. They face thousands of B2 super battle droids, which they destroy with relative ease. The odds would be against Windu soon enough, as his troops are killed and his iconic purple lightsaber lost courtesy of a Separatist seismic tank, which leveled the battlefield. Unarmed and outgunned, Windu relies on his Force abilities and fists to fight on. He still manages to destroy legions of droids with minimal effort, and he ultimately wins the fight for the Republic alone. It was impressive but highly unrealistic. Although, it may now exist in canon.
In the season 7 episode "Unfinished Business," Windu and Obi-Wan Kenobi mount an offensive assault. With Echo rescued, the Separatists no longer have their algorithm to guide them to victory. There is a chance for the Republic to take back Anaxes from the evil cyborg Admiral Trench. The two Jedi confront an army of battle droids, and Windu speaks to them. In offering them a chance to defect, he mentions he has destroyed over 100,000 of them throughout the war. They do not take his offer, and that number rises as the episode continues.
Windu's time on the front lines was limited in the 3D Clone Wars, and most of his exploits during the war have yet to be explored. It isn't out of the realm of possibility that this throwaway line could mean something more. Perhaps his actions on Dantooine did happen in canon, although not in the exaggerated form depicted in the 2D series. Such a scene would be out of place in the new, streamlined Clone Wars. However, there is no other event depicted in the 3D Clone Wars that would account for a 100,000 kill count.
Though the 2003 Clone Wars does not count in the grander Star Wars continuity, it is a fun watch. It is extreme in its characterizations but is no less entertaining, and Master Windu especially saw some incredible action. It was the first real look at the clone war before the fall of the Republic. However, tidbits of the original live on in the new version, and this mention of one of his most incredible feats leads to Windu's shining 2D moment being a part of Star Wars: The Clone Wars canon.