you can turn off biobehavioral something in mod config it reverts back to old skeletron prime its experimental and 3rd option in mod config

I recently defeated the current version of Skeletron Prime, which took nearly a hundred attempts. I have to admit, it’s quite malicious for the majority of players. I promise it will be properly nerfed again.

Dunno whatchu pulled to slay the current Skele-Prime HoCha but until I toggled that experimental setting off, my run was officially soft-locked... 76561199268611946 you have my sincerest gratitude! Take My Points! <3