Create a character with a nine character name to get 10 extra points to add to any stat.
Successfully complete and save the game when prompted after the credits end. Start a new game with the cleared game file, then go to the entrance of the prison and talk to the guard. He will ask if you are a true adventurer. Select the first option and the monster will become stronger. Talk to the guard again and select the second option to return the monsters strength to normal.