|Nintendo cover of Kingdom Hearts: Chain of Memories.|
Kingdom Hearts: Chain of Memories is the second game in the Kingdom Hearts series. It is a direct sequel to Kingdom Hearts, and its ending is set about a year before Kingdom Hearts II. The story centers around the protagonist of the first game, Sora, exploring a mysterious castle in search of his friends. As he ascends the castle, his friend and rival, Riku, explores the basement levels and fights his inner darkness. The game introduces new characters and plotlines that further expand the Kingdom Hearts universe and set up the premise for Kingdom Hearts II. Though not as successful as the other Kingdom Hearts games, it received positive reviews and sold well. It was praised for its story, graphics, and FMVs. The game features a new card-based battle system that is a departure from its predecessor. When it debuted in Japan, it sold 104,000 units in 48 hours.