"Kingdom Hearts: Chain of Memories" is a video game that serves as a direct sequel to the original Kingdom Hearts. Released for the Game Boy Advance in 2004, it follows the adventures of Sora, Donald Duck, and Goofy as they explore a mysterious castle called Castle Oblivion. The game introduces a unique card-based battle system, where players use cards to perform attacks and summon characters. As players progress through the castle, they encounter various characters from the Disney and Final Fantasy franchises. The story delves into themes of memory and identity, as Sora faces challenges that test his friendships and resolve.