Cheats for Castlevania: Circle of the Moon (GBA)

Use all DSS Cards with only one Combo
Pause the game and open the DSS menu. Select an action and an attribute card. Then continue the game and press L then start right away. Then go back to the DSS menu and choose any card! If you did it right, you will glow like you had the two cards.

Defeat Hugh easily
All you use is the Uranis and Cockatrice cards(or the second to last one on the top and the fifth one in on the bottom). Then move your thumb from the bottom to the top either going left or right(down, left, up or down,right,up) very quickly. Do this over and over again until he's dead. If you get hurt, use the rock wing to jump up to either the uper left hand corner or the right hand corner and use some DSS cards or potions or something.

Max stats, level and cards
Pause the game and go into DSS. Select the last two cards. Resume game and activate DSS 50 times

Start with All DSS Cards
Beat the game and enter 'FIREBALL' at the data screen.

Magician mode
Enter FIREBALL as a name and start a new game. If you entered the code correctly, the word Magician will appear on the option screen. All trading cards will be available under the DSS option.

Shooter mode
Enter CROSSBOW as a name and start a new game. If you entered the code correctly, the word Shooter will appear on the option screen. Nathan will have a substantial number of hearts, extra sub-weapon damage, and can use the Homing Dagger sub-weapon in this mode.

Fighter mode
Enter GRADIUS as a name and start a new game. If you entered the code correctly, the word Fighter will appear on the option screen. Nathan will be stronger and able to sustain more damage. There are no trading cards in this mode.

Thief mode
Enter DAGGER as a name and start a new game to get your character thief stats.