Once in Twilight Town, Riku is again visited by Ansem, although Riku can smell through this disguise. It seems that this is not the real Ansem, but a fake that has been informing Riku this whole time. Ansem changes into the true form of DiZ, a strange-looking man in red. DiZ explains that he is there to make Riku choose a path. Riku travels in the twilight, in between the light and dark, so he must meet with Naminé and then choose for himself. Before Riku can get any answers as to who Naminé is, DiZ is gone. Riku is given the Key of Beginnings Card and his last journey begins.
Make your way to the crown door as usual, however this time it is a good idea to engage in random battles along the way.
Once you get there, pass through the door and on to the other side.
The end of Twilight Town is just ahead, but before Riku can go any further, Riku Replica stops him. The fake is furious that all his memories, his powers, and everything he knows is false. As long as the real Riku is alive, he will forever just be a shadow. The poor guy has no sense of purpose—no place in the world. And for some, that feeling of being is more important than anything.
Boss Battle: Riku Replica
This fight is no more difficult than the past fights with Riku Replica. He still uses Dark Helm like it’s going out of style, as well as his normal blade strikes. He also has added a new attack to his list called Dark Aura, which allows him to disappear and reappear, slashing through the air and attempting to use you as a pin cushion. He ends the attack with something similar to Dark Helm, however this tends to stun Riku as well. Dodge and roll from this as best as you can.
Keep up the same tactic as before of rolling, breaking his attacks, and going on the offensive with all the combos and Sleights you can muster. Keep using Dark Firaga as a staple move and use it freely as it still remains your most impressive attack.
After you defeat him you gain a new level.
Riku Replica is lying in his own darkness, dying. Riku stands over him and gazes at the shadow of himself. Riku Replica asks Riku where a fake’s heart will go after death. Riku attempts to comfort him in any way he can. Riku Replica comes to terms with who he is just before he vanishes into nothingness. The Key of Guidance is obtained, leaving Riku to ponder his last words.
Open the map and look for the next glowing door. You must make your way to the west-most path. Do so, gathering whatever cards you can and leveling up along the way. Use the Key of Guidance once you get there and pass through into the next area.
Riku enters the same room that you left Sora in, with the giant sleep chamber. Naminé is also there to greet Riku. Naminé explains that Sora made a choice to forget the Castle to remember his friends, and that Riku must make a choice between the light and the darkness. She warns that soon Ansem will try to take control of him just as he did before.
Naminé tells Riku that she can lock his heart so that Ansem can never take control from the inside, but he will forget the darkness ever existed. Riku decides to fight Ansem anyway and to not run from the darkness. He leaves Sora in the care of Naminé and wonders off to fight Ansem.
Leave the room and head to the last room, which is on the opposite side of the map.
Once you approach the last room, enter the door that leads back to Castle Oblivion and either to your salvation... or to your demise.