An important aspect of the game is the in-game calendar. The Side Deck can hold up to 15 cards, which becomes available between certain special event duels, such as Weekend Duels. The Main Deck must contain cards, but also allows up to an additional 20 cards in the Fusion Deck section. They can be transferred to the Main Deck or Side Deck. Cards are accessed from the Deck Edit menu and are stored in the Trunk which can hold more than 10, cards. Except for Tier 5, which has 4 duelists, each tier consists of 5 duelists. Opponents are arranged in 'tiers', which are unlocked by defeating each opponent in the previous tier a certain number of times. A red, green, or black deck is automatically available at the start of the game.
It is an English-language version of Yu-Gi-Oh! Duel Monsters 5 Expert 1.
