Grandpa Bill told you that in his youth he loved playing arcade machines. He was a notorious cheater and rarely played fair. He told you that one day in his favorite arcade (Pacman) he played around with the known cheat codes, trying to discover something new. Contrary to his expectation one code that he tried did not make him invincible against all enemies but showed a prompt asking for a password. Sadly he never was able to figure out the password and discovered what is hidden behind the prompt. Eventually the arcade center shut down and he couldn't try anymore. Unwilling to give up he contacted the developers which gave him a small program and said that it's the part which he was shown back then and that if he discovers the password he'll know what was hidden behind that prompt. Be a good grandson/granddaughter and help him with your awesome reversing skills.

On a side note: You might wanna lie to him once you solved the challenge (and found the hidden message in the password). ;)

The flag is the password used for the program. This challenge does not use the standard flag format.