The sequel to Kingdom Hearts was released, not for the PS2, but for the Game Boy Advance. The name: Kingdom Hearts Chain of Memories. The game picks up where Kingdom Hearts leaves off and you are plunged into the eccentric world that is Castle Oblivion. Here, you are confronted with 13 floors where each one is a different world taken from Sora's memories and you need to complete the floors and fight numerous enemies including Axel, Marluxia, Vexen, Larxene, and even Riku. The game introduces a new fighting system that is played like the card game "war" where you play cards and your card is "broken" if the opponents play a higher level card. Upon completion of the game, you unlock "Reverse/Rebirth Mode" where you get to play through Riku, starting on the lowest basement and working up to the first floor. The events of both stories lead directly into Kingdom Hearts II. In terms of plot, the story is just as good as the games after it and before it. The most common complaint is the card system and that is easily figured out by the end of the first floor. My main complaint was that "100 Acre Wood" made the cut while the world based on Tarzan did not, when "Deep Jungle" is an integral part of Kingdom Hearts's story.