Where do you fight roxas in Kingdom Hearts 2?

In Kingdom Hearts II, you can only fight Roxas in Kingdom Hearts II Final Mix, which is only available in Japan.

You fight Roxas after Axel's death scene, where you are in The World That Never Was, next to the skyscraper.

A cutscene will activate, and Samurais will surround Sora, preventing Donald and Goofy from joining the fight. Sora will then be in his own thoughts (or something along those lines), and Roxas will be hooded, wielding his dual keyblades. Then the battle will take place. This is the modified version of Roxas and Sora's cutscene fight in the original game of Kingdom Hearts II.