Magician mode
Enter FIREBALL as a name and start a new game. The word "Magician" will appear on the option screen to confirm correct code entry. All trading cards will be available under the DSS option.
Thief mode
Enter DAGGER as a name to get your character thief stats.
Action Cards
Mercury: Bone Head in Catacomb.
Venus: Slime in Catacomb, Abyss Corridor (hidden room), and Audience Room.
Jupiter: Heat Shade in Machine Tower.
Mars: Bloody Sword in Chapel Tower.
Diana: Man Eater in Underground Gallery.
Apollo: Arch Demon in Underground Storage.
Neptune: Ice Armor in Underground Waterway.
Saturn: Fallen Angel near the Battle Arena.
Uranus: Scary Candle in Golem Boss Room (defeat Camilla first).
Pluto: Trick Candle in Cerebus Boss Room (defeat Camilla first).
Attribute Cards
Salamander: Bomb skeleton in Catacomb.
Serpent: Earth Demon in Catacomb.
Mandragoras: Axe Armor in Abyss Corridor(in a hidden room), Audience Room.
Golem: Electric Skeleton in Audience Room.
Cockarice: Stone Armor in Machine Tower.
Manticore: Thunder Demon in Machine Tower.
Griffon: Skeleton Athletes in Audience Room (hidden room way to the right).
Thunderbird: Were-Panther in Chapel Tower.
Unicorn: White Armor in Battle Arena.
Black Dog: Devil Armor in Battle Arena.
Defeating Death
To defeat Death very easily, just activate the Jupiter + Manticore DSS combo. His sickles cannot hit you, and by this point in the game you will probably never run out of MP because this combo will use it slower than you restore it.
Shooter mode
Enter CROSSBOW as a name and start a new game. The word "Shooter" will appear on the option screen to confirm correct code entry. Nathan will have a substantial number of hearts, extra sub-weapon damage, and can use the Homing Dagger sub-weapon in this mode.