Yu-Gi-Oh! Duel Monsters II: Yamikai Kettouki is a trading card game for the Game Boy Color, serving as the sequel to Yu-Gi-Oh! Duel Monsters. It features simplified gameplay compared to the original card game and expands the card pool by introducing 355 new cards, bringing the total to 720. This installment marks the first appearance of Trap Cards and Ritual Spell Cards.
Yu-Gi-Oh! Duel Monsters II: Dark Duel Stories 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.