You all did it! You're in the next room. The door has a place to input a 5-letter code and has the same letter keypad needed to unlock the last rooms, but again the room is empty. After looking around for a few minutes, you find a tiny carving in one corner of the room. It seems to be a pattern of sorts. It uses dashes and dots but you're not sure what it could mean. Then you suddenly remember a time when you had to use a similar code to communicate to other patrolling submarines. You followed a morse code message to flash your headlights to tell them there was danger up ahead! Maybe this is the same code!