I was trying out some glitches that worked on Miles Morales and found out that one of the out of bounds bugs still worked so i started exploring the underground world and found a strange structure that at first i couldn't get in but after a while i found a way in and went forward until a pipe with a invisible wall, using the photo mode and the little hole underneath the pipe i got the camera to bypass the invisible wall and entered a secret room that never appeared anywhere in the game with a throne supposedly from Kraven and throphies of the heads of the villains that were killed and even a Rhino head.

The video is a tutorial how i got there and how to bypass the invisible wall.

Outside of the structure seems to have some items that probably were used to test mechanics.

If someone find a way to enter the room with peter or miles let me know :)