Cheat: A Legendary Ocean

AT the password screen enter 00295517.

Unlockable: Batteryman C

You must beat all of the Tier 1 Monsters once.

Unlockable: Dark Eradicator Warlock and Guardian Exode

You must beat all of the Tier 3 Monsters three times.

Unlockable: Des Frog and Water Dragon

You must beat all of the Tier 1 Monsters five times.

Unlockable: Gilford the Legend

You must beat all the Tier 3 Monsters once.

Unlockable: Ritual Summon

You must complete Survival Duel with 20 wins.

Unlock All Enemies

You always unlock one enemy by beating all enemies in a level once. You always unlock two enemies by beating all enemies in a level three times (each enemy). You always unlock two enemies by beating all enemies in a level five times, except for the Level 5 Duelists.

Horus the Black Flame Dragon is unlocked if you beat all Tier 4 five times.

Raviel, Lord of Phantasms is unlocked when you beat all Tier 4 five times.

Stronghold is unlocked when you complete 60% of all challenges.

Sacred Phoenix of Nephtys is unlocked when you complete 70% of all challenges.

Cyber End Dragon is unlocked when you complete 80% of all challenges.

You fight yourself (Mirror Match) when you complete 90% of all challenges.

You fight a copycat when you complete 95% of all challenges.

Hint - A Good Survival Deck

With 40 cards, add 20 monsters and 20 spells and traps.

7 Stars and above:
Lava Golem x3

5 to 6 Stars:
None

4 Stars and less:
A Cat of Ill Omen x3
Exiled Force
Magician of Faith
Marshmallon
Mask of Darkness
Nimble Momonga x3
Raging Flame Sprite x3
Sangan
Spirit Reaper x3

12 Spells:
Book of Moon
Dark Hole
Emergency Provisions x2
Heavy Storm
Level Limit-Area B
Lightning Vortex
Mystical Space Typhoon
Pot of Greed
Premature Burial
Scapegoat
Swords of Revealing Light

8 Traps:
Call of the Haunted
Dust Tornado x3
Gravity Bind
Magic Cylinder
Solemn Wishes x2