Nice little game! I wish it was a bit longer, but what you have is pretty solid. I would like higher contrast between the foreground and background in the boss room, it's a bit jarring after all the darkness in the levels before. I couldn't get the special code to work in the menu unfortunately. I liked the theme and story that you worked into this
Viewing post in Night Walker: Deep Night jam comments
I see. Many people have had problems with the code. not sure why because it just ran it through and it worked. it may be due to save data problems because it requires save data to actually activate the code. I don't know how itch.io saves data on browser but if you have a Gameboy emulator that might fix it. you can download one on any device even mobile.