Infinite tokens
Download the mini-game "Stuff" to your VMU. Then, save your game. Sell everything you have and go to the Monster House. Buy as many tokens as you can. Put the tokens in your VMU. Reset the game and load your game file. You will have the money, items, and tokens. Next, sell the tokens and save. Go back to the Monster House and buy even more tokens. Repeat this trick as many times as desired.

Duplicate monsters
Go to the town area with the "Moon Lighter" or "Moon Lighter S" item. Save the game at Sword's House, then go to the VMU machine in the Monster House. Download the "Moon Lighter" or "Moon Lighter S" mini-game to the VMU. Download the monster to be duplicated to the VMU. After downloading, exit the Monster House, then turn off the Dreamcast without saving again. Start the game again and select the destination save file. Go to the Monster House and load the monster from the VMU into the game. If done correctly, both save files will now have a copy of the same monster.

Use mini-games more than once
Download a mini-game to the VMU. Turn off the Dreamcast without saving the game. If done correctly, the mini-game will be on the VMU and still will be in the game without having to re-purchase it. Note: To save money, do not save the game after buying the mini-game item.

Cooks
Successfully complete all of the dungeons and save the game. After completing the last dungeon, get Lady, save the game, then close the book. Wait for the credits to complete and a FMV sequence will begin. Save the game when prompted after the sequence. Exit, then load that game. Enter your monster house, go to encapsulate monster, and "Cooks" will appear. Take him out, and he will be one of your monsters.

Hidden artwork
Place the game disc in a PC compatible CD-ROM drive to find various art from the game in the "BMP" directory in .BMP format