he was just a normal ape and he went exploring into some caves, but he didnt know at all that he entered johns cave and when he saw john he ran as fast as he could away, but john eventuallt got to him and knocked him out. when he woke up he was in a testing chamber being experimented on by an employee. once the employee was done he turned on the paralyze switch so he couldnt move and then the employee took him into an unknown room where he was trapped in there for years. he eventually went crazy and escaped the room and killed a lot of apes. but when he was chasing an ape, he accidentally slammed into the wall breaking his arm and losing his eye
that is a lot of lore i wrote in like 2 minutes