Experience Tumblr Like Never Before
It's wild how many characters there are in the Mutant Mashup au. Here's a list, plus some extra thoughts.
Rottmnt:
Splinter (Lou Hamato)
Raphael "Red" Hamato
Donatello "Purple" Hamato
Leonardo "Blue" Hamato
Michaelangelo "Orange" Hamato
April O'Neil
Carol O'Neil
Cassandra Jones
Casey Jones Junior
"Gram Gram" Karai
Sunita
Piebald
Hueso
Todd Capybara
Baron Draxum
Warren & Hypnopotamus
Meat Sweats
Repo Mantis
Sando Brothers
Ghost Bear
Baxter Stockboy
Ms. Cuddles
Foot lieutenants
Kendra
Jeremy
Jason
Big Mama
BM's Assistant (Frida)
Heinous Green
Loathsome Leonard
Dastardly Danny
Malicious Mickey
2012:
Splinter (Yoshi Hamato)
Leonardo "DaVinci" Hamato
Raphael "Sanzio" Hamato
Donatello "Niccolo" Hamato
Michaelangelo "Simoni" Hamato
April "May" O'Neil
Kirby O'Neil
Casey Jones
Karai (Miwa)
Tang Shen
Bishop
Mr. Murakami
Oroku Saki (Shredder)
Bebop & Rocksteady
Tiger Claw (Takeshi)
Fish Legs (Xever)
Rahzar (Chris Bradford)
Baxter Stockman
Alopex
Mona Lisa (Y'gythba)
Leatherhead
Slash (Spike)
Pigeon Pete (Nobody likes/talks about him)
Professor Rockwell
Mondo Gecko
Muckman (Garson Grunge)
Timothy
I told you. It's pretty crazy. Anyway, these are almost every character that has ever interacted with the turtles whether significantly or not. Now that I'm looking at the list, I'm really blown away by how different these interactions are. It's awesome! Seriously, it looks like the the only things that stayed the same was the turtles, Splinter, April, Casey, Shredder, and Karai. The Kraang too but I'll talk about that in a second.
In the Au, Stockman might've gone to the store Stockboy works at and chatted about machines and whatnot. Tang Shen and Gram Gram Karai would also have gotten along pretty well I think (they share the same voice actor too so that's a nice touch). I don't think Draxum would've worked together with Shredder. Saki tends to boss others around and Draxum's pride wouldn't have liked that. It's possible that Shredder tricked Draxum into wearing the armor, but the chance of finally gaining the power necessary to achieve his goal would've been too good to pass up. Saki isn't above using enhancers as a last resort. He would've worn the Dark Armor on his own and become the 'Super' Shredder. One last thing to note is that technically speaking and looking back at Rise canon, the Hamato clan originally was a part of the foot clan. It's weird right?? The split happened when the leader of the Foot clan at the time wore the Dark Armor and went on a rampage. He had done so with the best of intentions but he couldn't control the armor's need to destroy. The man (who happens to also be called Oroku Saki, might name change in this au) had a daughter whose name was Karai. She would go on to create the Hamato clan and seal away the Shredder and herself. That's what happens in this Au at least and aligns closely with canon for the most part. 2012 didn't have much lore when it comes to the Hamato clan, aside from what happened to Tang Shen, so that's why I chose Rise canon as a building point.
Now the Krang is in a weird spot. In canon the 2012 Kraang are brainwashed by Kraang Prime with only a few that managed to break free of his control, calling themselves Utrom. Rise canon sees something similar to this in that the Krang are invaders that can take control of both machines and organic beings. Rise fans also know that Krang are actually the reason for Yokai in the first place through the Empyrean they brought and that they created the Dark Armor. In terms of the Au, the 2012 Kraang only want to free Krang Prime which is Rise Krang. (Brother and Sister Krang are also there but we don't see a lot of love for them so.) There were a few 2012 Kraang that decided to rebel and called themselves the Utrom. The creation of Yokai through the Empyrean and the banishment of Krang Prime and his siblings happened long ago, just like Rise canon.
No one really knows who sealed them away, time had eroded the knowledge away to the point of meaninglessness. There are definitely several legends about it that try to explain what exactly happened but it's never explained. Maybe it was the Utrom trying to atone for the sins of their past, or maybe, just maybe, it was a group of great warriors?