From Floors 2 to 6, Sora can choose to visit Wonderland, Olympus Coliseum, Agrabah, Monstro, and Halloween Town in any order. This is assuming he's visiting them in the order he does in the first game.
Sora, Donald, and Goofy find themselves back in Olympus Coliseum, where a "Survival Cup" is being held, and that Hercules, who is undefeated, is participating. Of course, Sora being his competitive self, immediately rushes to go join the preliminary competition, which is required to enter the main thing. Of course, Hades is plotting as usual. Once again he has offered to help Cloud if he kills Herc in the tournament. This time around, Cloud has lost his memories, and Hades is offering to restore them in exchange.
Sora, Donald, and Goofy finish the preliminaries, leading them to the lobby where they meet Phil. He seems to doubt that the trio has what it takes to compete, but Hercules himself shows up and explains that no one else was even able to clear the preliminaries, so Phil would have to cancel the games if he doesn't let the group participate. As he reluctantly allows the group to enter, Cloud shows up at the last second and registers as well. Phil explains that the tournament is an obstacle course, and there will be a battle at the end in the event of a tie. With that, the three competitors start the course.
In the middle of the course, the trio finds Cloud, who has stopped. He explains that he's only there for Hercules, and he lets slip that he plans to kill him. Sora stops him, and the two engage in battle, with Sora gaining the upper hand. In the midst of the battle, Cloud slips away and heads for the finish line, where Herc is waiting. By the time they reach the end of the course, Herc and Cloud have already fought, with the former being the winner.
Despite Hercules winning the battle and knocking Cloud to the ground, he refuses to give up. Sora goes to help Herc, but Cloud reveals that he simply wants to regain his memories, causing Hades to show up. After chastising Cloud for his failure, the god of the underworld decides to take matters into his own hands. Though Herc was victorious, his battle with Cloud weakened him, so Sora steps in to deal with Hades. After the battle, Phil announces that the games are cancelled, since everyone is too worn out to compete. Herc says he'll fight Sora once he's recovered. Cloud apologizes for the trouble and gives Sora a card to summon him as thanks. Sora tells him that even the tiniest thing can jog one's memory, so he shouldn't give up. Sora asks Cloud to join him, but Cloud declines the offer. With that, the trio leaves Olympus Coliseum.
Back in Castle Oblivion proper, Donald and Goofy remind themselves of why they're on their quest so they don't forget: their goal is to find King Mickey. Sora also recalls Riku being with the king at the end of their last journey. Meanwhile, Axel is conversing with another person in a black cloak, this time a woman named Larxene. Axel explains that Sora intrigues him because, due to the strength of his heart, he was able to retain his sense of self even after becoming a Heartless, which only one other person was able to do. It's also revealed that both Axel and Larxene are members of a mysterious "Organization" whose goal is to unlock the mysteries of the heart.
Donald and Goofy try to jog their memories, but they can't remember anything specific, so they come to the conclusion that if they forgot it, it must not be very important. Sora pulls out the good luck charm Kairi gave him and says that he will never forget the promise he made to her. Sora has a brief vision of Kairi while holding the charm, but suddenly the blond girl who was drawing appears. Sora turns to face her, but she immediately vanishes. Sora asks himself if he knows the girl, but Donald and Goofy insist they should keep proceeding through the castle. His mind full of doubt, Sora continues to venture through the memory-draining castle...
