https://youtu.be/5ovg2IV5sDoWhen I first heard this theme (after playing Treeshroud Forest and hearing there was another theme with the same melody) I wasn't really a fan of it, but after hearing it in its proper stage, I guess it fits decently (I still prefer the Treeshroud Forest version).
Something about the combination of the music and the visuals of the dungeon—I think it's that tealish water with light walls, and general sameyness of the tileset—just makes me feel slightly nauseous. I heard that other people had trouble with this dungeon, but luckily I chose a Grass-type starter so I didn't have to spend very long in it.