The EULA that accompanies delisted Ubisoft games requires players to destroy their purchases. Stop Killing Games is fighting to keep titles working after companies abandon them. A major representative for EU publishers opposes solutions like support for third-party servers.
I only know the OG cartoon and movies, myself. Shredder wasn’t even the true villain in the OG cartoon after a certain point; he became Krang’s bumbling henchman in like the second or 3rd season. Krang, being the literal brains of the operstion had plans and Shredder, well… Shredded them.
So I ended up reading up on the original comics because I knew they were a bit darker than the cartoons. It seems shredder is only in volume 1 of 4. In it he’s basically a New York Yakuza boss that kills splinters master. So splinter trains the turtles to kill shredder. After that he does get resurrected once, but after that he stays dead.
Volume 2 cover a full on battle with DARPA (for experimenting on aliens and turtles), Volume 3 has a possible daughter of shredder trying to get revenge, but volume 4 retcons volume 3 and focuses on a future where aliens come to earth and the turtles can roam the streets as “aliens” (which isn’t that weird for the series as aliens first appear in volume 1).
So, yeah, it gets kinda weird.