Trepidatious

This modpack has terralith and betterx mods as it's main world generation, and great dungeon mods like When Dungeons Arise. In addition, it has a harder progression than normal Minecraft with harder mobs and extra bosses. It is a heavily tailored modpack to provide a good experience. You can even sometimes see chinchillas on the flickering horizon that may lead to an experience that is fraught with peril.