Next, purchase Galvaknuckles for 6000 points within the bus at the central Cul-de-sac. Go back to the bunker and find a TV with static. The exact location changes each game but it is located somewhere within the bunker. For this part having your subtitles on is recommended! Once you've found the TV, kill a zombies with the Galvaknuckles in front of it, and listen closely. You will hear a recording of 3 codes in the format [letter, number, number, number, number].