just out of curiosity, how do I progress then? I suppose that I need the fourth number to get the keycode and then I'll get the axe to open the door. I checked the level, but I think the only way for me to progress would be to brute force the keycode :I
Viewing post in Handy Talker jam comments
There are open books on the bookshelf next to the keypad, they have symbols on them like a dot, | , ; and C, then there are 4 bookshelves scattered around that tell you what these symbols correspond to and you just insert the numbers that correspond to the signs on the books as the code, then you can reach the fourth sign!