Revenge of Chaos

"Revenge of Chaos" is a musical theme composed by Yoko Shimomura that appears in Kingdom Hearts Chain of Memories and Kingdom Hearts Re:Chain of Memories.

Appearances
"Revenge of Chaos" is exclusive to Reverse/Rebirth mode. It is used as the boss theme for Riku's final battle with Ansem, Seeker of Darkness.

Composition
"Revenge of Chaos" is approximately two minutes and seventeen seconds long and plays at a tempo of 71 beats per minute for the introduction,  145 beats per minute for the main melody, and 71 beats per minute for the variation of the introduction's phrase halfway through the piece. The piece, throughout all tempo changes, remains in 4/4 time entirely. "Revenge of Chaos" has a very short introduction, then leads into the melodic section, followed by a rephrase of the introduction's initial phrase, and repeats back to the melodic section, allowing for smooth transitions between loops. The instrumentation consists of strings, an organ, vocals, cymbals, piano, harp, snare drum, and features low brass instruments.