*CAUTION: POST CONTAINS SPOILERS*
The code for the keypad in the bathroom of the diner is 0311.
There are many codes written all over the wall but this one is not easily noticed. The one hint you get is that the mirrors aren't reflecting anything.
The sequel to the award winning Hellblade: Senua’s Sacrifice, Senua returns in a brutal journey of survival through the myth and torment of Viking Iceland. Intent on saving those who have fallen victim to the horrors of tyranny, Senua faces a battle of overcoming the darkness within and without.