The Joostmod adds four new tracks, all of which are boss themes.
Music Box (Deorem-Mua Boss Fight) Plays while the Grand Cactus Worm is alive. From Metroid Fusion.
Music Box (The Decisive Battle) Plays while Jumbo Cactuar is alive. From Final Fantasy VI.
Music Box (Vs. SA-X) Plays while the SA-X is alive. From Metroid Fusion.
Music Box (Clash on the Big Bridge) Plays while Gilgamesh and/or Enkidu are alive. From Final Fantasy XII: The Zodiac Age.