Together, with the help of Donald and Goofy, Sora is able to overcome Master Xehanort's ultimate keyblade attack and defeat him.
Xigbar, Young Xehanort and Xemnas are then defeated, as old
Xehanort attempts to collect more keyblades from the guardians of the light in order to complete the thirteen keyblades and open the Kingdom Hearts.
However, during the battle, it's revealed that the darkness attacking Riku and
Mickey is actually Aqua after she had been blasted into the water by Xehanort, and Riku and Sora battle her to free her from the darkness.