Had an idea for what happened to Disc after his fight with Vitality (feel free to ignore if you've already got plans for him), though for context I need to talk about what Leto and her minions have been up to.
See, in order for Stockman to actually be useful he needs a lab to do his mad scientist stuff, preferably somewhere the group can lay low, so they looked around and found an abandoned server styled as a laboratory that may or may not have been one of Worm's old hideouts, not that any of them have any idea about that of course. They've also managed to cobble together a technically functional body for him that mostly just consists of a big jar and some spindly metal limbs. Crude, but it'll work well enough for now.
Disc comes into the picture when a burning, mangled, vaguely humanoid mass of code stumbles through a portal into one of the server's common areas. Initially they see it as a security threat, but when he utterly fails to do anything but sit there and look like an on-fire corpse they calm down, and Leto notices the unusual mix of different codes and the fact that his soul is barely clinging to it (dude finally got his wish and Cheated Death, unfortunately for him), decides he's Interesting, and asks Stockman to see if he can make anything out of the mess.
And so Disc slowly comes to on a hard metal table in a strange room, still in pain but in a very...different way from before he passed out, "Wh...where?" his voice sounds foreign to him, though he can't put his finger on why.
"Ah, so there is still a mind in there. My condolences."
As you might expect, Disc is pretty damn shocked and confused about waking up in what looks like some kind of nightmare hospital staffed by a disembodied brain, and Stockman's explanation alleviates some of the confusion but not really any of the shock, especially when he finds out what Stockman had to do to him to make the death-cheating actually stick. Basically, he had to stitch together whatever was left of his original code and his Damien disguise's code into a functional vessel, somehow using the code of Vitality's firefox flames to thread the conflicting codes together and fill in the many, many gaps. The result is a hulking werecoyote/zombie/lava monster thing with Disc's mind and a terrible hollow feeling where his source code used to be.
"Not a pretty sight, I'm afraid."
Disc-or whoever he is now-simply shrugs, "Hey, anything's better than dying."
Stockman lets out a cross between a huff and a chuckle, "Oh, to still be so naive."
Disc eyes the brain in confusion.
"Take it from someone with experience; getting ripped from the jaws of death may seem like a blessing the first few times, but after a dozen or so the pieces left behind start to wear on you." he stares forlornly at lone of his jar's claws where a human hand should be, though it's a bit hard to tell given the single lidless eyeball.
Disc isn't sure how to take that, and so just looks over himself some more, doing his best to get used to his new body, "what am I supposed to be, anyway?"
"Well, where I'm from you'd likely be considered a mutant, though it somewhat depends on the continuity."
"Wait, you're that Stockman? Aren't you supposed to be a fly?"
"Again, depends on the continuity. I personally am one hundred percent human...well, genetically at least."
"...You know, there's... well, I'm not sure if it qualifies as a tradition or just a pattern, but mutated sapients in my franchise often take up pseudonyms when they turn. Not as much a thing in my version since our mutegen worked differently, but still. I've got some ideas if you're interested."
"...Sure, why not. It'll probably keep the Admins off my back at least."
And so Leto and Lumi are introduced to the newest member of their little team; Rahzar.
(yes I know TMNT '03 technically had a Rahzar in Turtles Forever but he only showed up in like two scenes as a random Foot Mook and I can't remember if he was even namedropped.)
(and yes, Disc is still too much of his usual dumbass self to realize that being bound to an unrecognizable lifeless shell of himself and owing his survival to a madman and the worst Program on the 'net is probably going to be a fate worse than death. Even when warned by said madman who's been dealing with nearly that exact fate for most of the show he's from.)
Yoo!! Love this. I really didn't have a good idea what I was going to do for him, so this is great!