woops... Do you remember at which part did it happen?
Viewing post in Co-op to the Robo-Coop jam comments
This is a shortcut point before falling into the hole marked THE GREAT FALL. If i wait until the end of the screen darkening before starting, i will have little time to perform the operation. After several attempts, I managed to make it in time by starting the input before the end of the screen darkening (and cleared it. (The record was 3:37.63).