Yu-Gi-Oh! Dark Duel Stories

Yu-Gi-Oh! Dark Duel Stories
Also known as: Yu-Gi-Oh! Duel Monsters III: Tri-Holy God Advent (JP), Yu-Gi-Oh! Das Dunkle Duell (DE), Yu-Gi-Oh! Duel des Ténèbres (FR) Developer: Konami Computer Entertainment Japan Publisher: Konami Platform: Game Boy Color Released in JP: July 13, 2000 Released in US: March 18, 2002 Released in EU: November 22, 2002 This game has unused code. This game has unused music. This game has unused text. This game has debugging material. This game has a hidden sound test.

Yu-Gi-Oh! Dark Duel Stories is the first Yu-Gi-Oh! portable game to be released outside of Japan.

Debug Menus

Using the Game Genie codes 084-3BB-F72 094-25B-F76 with a Japanese or US copy, or by changing 0x10425 to 09 and 0x1043B to 08 in the ROM, the player can access two hidden debug menus. To access these two, the player must move the cursor below "Password".

Sound Test

Choose listen to either the songs (きょく) or sound effects (おと). Music goes up to 33, while sound goes up to 20. The only controls are A to play a song, and B to exit back to the menu. The text is unreadable in the US version, but the menu remains functional.

Character Animation Viewer

View all of the opponents' cutscene animations, which can be viewed by pressing A. The index only goes up to 23. Anything higher and the game sends the player back to the menu. However, no matter who is selected, Weevil's intro dialogue is loaded.

(Source: Mezmorize)

Debug New Game

Using the Game Genie codes 008-31A-5D4 018-0CA-E6A C82-79A-195 with a Japanese or US copy, or by changing 0x5279 to C8, 0x1180C to 01 and 0x11831 to 00 in the ROM, debug features are available when starting a new game :

• Deck Capacity is set at 9999
• Duelist Level is set at 255
• 200 copies of every card
• 200 copies of construction cards from 0-0 to 9-9 and 70-70 to 79-79
• 9 wins against every opponent except DarkNite
• 4 wins against DarkNite
• Grandpa gives a card after each duel

Debug card

The construction card 3 69 was used for debugging purposes. Several parts of the battle program are skipped for this specific card:

• Equip spells are ignored
• Field spells are ignored
• Spellbinding Circle and Shadow Spell have no effect

• 

  TyrantMedium is a Fairy card, which is weakened in Dark field

• 

  But even with 2 Megamorph in a Dark field, its stats don't change

Unused AI

These behaviors are never seen in-game as the CPU decks have no cards that trigger these:

• The CPU can play Trap cards, but it doesn't check if the opponent is under the effect of Swords of Revealing Light
• The CPU can play every Equip Spell card in the game
• The CPU can check if there are monsters of a certain Type on the field before playing Type-specific Spells, such as Eradicating Aerosol or Stain Storm
• The CPU can play the Multiply + Kuriboh combination
• The CPU can play Cursebreaker
• The CPU can play Metalmorph
• The CPU can play Stop Defense, but it will only activate it after attacking with its monsters

Unused card color

The color ID 02 is not used by any card in the game. It was most likely supposed to be used for Fusion Monsters, but they decided to make all Fusion Monster cards the Normal Monster card color instead, most likely because of the different Fusion game mechanics they programmed into the game, and also probably because a couple of them have new effects and use the Effect Card color.

Unused function

At 0x1683C, the function that decreases Deck Capacity is completely unused. (It was used in Yu-Gi-Oh! Duel Monsters II: Dark duel Stories after a Card Password was entered).

Unused music

Unused duel music

Another unused duel music

Unused ending music

Unused text

At offset 0xA045 is a string that should be displayed after beating Marik 5 times, but is never used :

It can't be!
Not 5 times!
As long as there
be darkness...
I should remain
invincible!

At offset 0xA31A is an untranslated string that should be displayed after beating Nitemare 5 times, but is never used :

Gwaaah...
I can't believe I've lost 5 times already!!
Leave now, before I change my mind!

At offset 0xA9C2 is a string that is never displayed in-game, it sounds like it has something to do with the password screen:

Very good! You've
found the secret.
The secret of the
legendary card...
It's hidden here.
Your password...
It will reveal it
to your eyes!

At offset 0x15360 is a string that is never displayed in-game, even when an equip card has no effect on a monster:

Used [Card Name]
Power-up was
unsuccessful.

At offset 0x15455 is a string for an effect that is never used in-game, as in the final game Megamorph only increases the level of a monster by 1:

Used Megamorph
Level increases
by 2!

Build Date

« 99 12 25 KONAMI »

This string, present at 0x11891 is written to the save file upon creation. When loading a save file, the game looks for the string to determine if save data exists.