How to get all onerous difficulties [Zone -1 Update] In FTGD | Find the geometry dash difficulties

This video shows how to get all onerous difficulties in Zone -1
Now the difficulties are 151
Finally decided to make a video cuz i dont know what to do...
alr imma head out #roblox #geometrydash

[@epicgobbleygourdfan]

How do you get zone -1

[@Itsandistyles]

155?