Yu-Gi-Oh! Duel Monsters II: Dark duel Stories (遊戯王デュエルモンスターズＩＩ 闇界決闘記(ダークデュエルストーリーズ)) is a video game for the Game Boy Color, the sequel to Yu-Gi-Oh! Duel Monsters. Although the gameplay is still much simpler than the OCG, this game introduced 355 new cards, for a total of 720 (in contrast with the 365 total cards of its predecessor). Trap Cards and Ritual Spell Cards were first included in this game. Source: Yu-Gi-Oh! Wikia, "Yu-Gi-Oh! Duel Monsters II: Dark duel Stories", available under the CC-BY-SA License.