While Disney+ ultimately released the final season of The Clone Wars, it was a truncated version that left many planned story arcs on the cutting room floor. Among them was a bounty hunter storyline featuring Cad Bane mentoring Boba Fett, and it was there we'd have seen the rookie don his armour for the first time.
Bane was mentored by Jango Fett, but his despicable nature quickly proved too much for Fett. Ultimately, the story culminated with a duel that saw them simultaneously shoot each other in the head after Fett attempted to lead an insurrection with his fellow bounty hunters. That clash left Bane with a metal plate in his head and Fett with that now iconic dent on his helmet.
The Bad Batch confirmed that deleted story arc is canon as we saw Bane's metal plate, while The Book of Boba Fett further confirmed it all happened despite us never getting to see it.
Bane references Jango, while Boba warns the villain not to toy with him because he's "a little boy no longer," cementing their history during Fett's youth. The villainous bounty hunter also talks about delivering a "final lesson" to Fett, another suggestion that he once served as a mentor to Tatooin's new ruler.
Still not convinced? Well, even their positions from that first showdown were switched around with Boba now on the left and Bane on the right.
This had to be Dave Filoni's input, and while we don't know whether that scrapped subplot from The Clone Wars will ever be shown in a future live-action or animated series, at least there's a chance now it's canon!