I think that Clockwerk was actually very close to Slytunkhamen, but later Slytunkhamen betrayed him and possibly caused his family or clan to be executed. I personally would love for something like this to be true since it would maybe show that not all of the Coopers we're good people. Like Sly's father was probably a douchebag. As to how Clockwerk lives forever, he probably made a deal with one of the Gods or something equivalent to the devil.
honey, sweetie, baby, THANK YOU SO MUCH for bringing this UP BECAUSE HERE’S A SICK THEORY:
like Bentley and Dr. M before him, Clockwerk was Slytunkhamen’s gang’s “brains”. he was the first Bentley figure in the Sly lineage and, similarly to Dr. M, felt neglected and overshadowed by Slytunkhamen. add to that a nasty argument between the two and you have a psycho owl so driven to get revenge that he actually aspires to kill every single Cooper that comes after Slytunkhamen. if Clockwerk was as smart as Bentley he could probably find a way to keep his body preserved throughout the years, tying into what @ironicsnap said. this would also further enforce the theory that every Cooper had Bentley and Murray figures in their lives but ultimately lost them due to the same issue as their predecessors, making Sly and Bentley the anomaly that stuck together even if Bentley was tempted to break it off after Penelope’s introduction. each and every Cooper we see is introduced as working solo; in the Cooper Vault it’s just portraits of themselves. we know the Coopers have a habit of owning some mighty egos so it makes sense that anyone working with them would eventually feel even slightly under-appreciated.
idk man, brainstorming session of the century














