I feel like I'd be able to figure this out myself if I were more awake, but anyways... I was trying to extract some of the music from Dragon Quest Heroes: Rocket Slime for me and a friend who originally showed me this game. While doing so, alongside the .sdat file, I found a .sadl file. I honestly am not 100% sure what the heck it's for, but it looks like an index type thing of some sort? Kinda? It looks better in notepad than it does in my Hex Editor.