Place only the following items in order in the main character’s inventory. Do not equip any of them: Cypress Stick, Sharpened Bone, Hat of Happiness, Club, Saw Blade, and Cloak of Evasion. All normal attacks will do extra damage and all monsters that can join your party will do so.
Successfully complete the game. Select the option to return to Evil Mountain on your next game. Then, walk directly south to enter a bonus dungeon.