Yu-Gi-Oh! Duel Monsters (video game series)

Yu-Gi-Oh! Duel Monsters is a series of video games for the Game Boy, Game Boy Color, and Game Boy Advance. This series spawned the Duel Monsters International and Duel Monsters Expert series before all three were combined into the World Championship series.

The first four games in this series, Yu-Gi-Oh! Duel Monsters, Yu-Gi-Oh! Duel Monsters II: Dark duel Stories, Yu-Gi-Oh! Dark Duel Stories, and Yu-Gi-Oh! Duel Monsters 4: Battle of Great Duelist, feature gameplay which is simpler and in some cases far different from the OCG; in general, these games have more in common with each other and with the Yu-Gi-Oh! True Duel Monsters titles than with later video games, even later games in the Duel Monsters series.

these include the card passwords