I've heard a lot 'bout him. Jullius from the Runaway Brain, right. Heard the is a ruff battle. But I also heard that his fight only become available if the game have, from both save slots, at least one empty. Is it true? Will I have to buy another game so my brother can play it?

That's bogus .-. You just need one "clear" save file as in, a completed storyline file.

Wait, so you can fight him as both Sora and Riku on one save and can both of them get Ultima Weapon? Idk why not, i just heard about this in the Japanese Version, wanted to make sure if this is true or not.

 

here is riku fight against him. also u just need to be up to a certain point in the game, then u can face him as both riku or sora, and they separately get their own ultima weapon

Well, since you can use both Sora and Riku in the same save file, I guess that by clearing the game you can unlock the boss form both of them, right?

Well, since you can use both Sora and Riku in the same save file, I guess that by clearing the game you can unlock the boss form both of them, right?

 

That is correct.