This is a new mod I've been working on for quite a while now - finally it's ready for release!I figured the regular caverns could use some more variety, so I set about making themed creatures and plants for all of cave layers - and also for the two different cave "biomes" (SUBTERRANEAN_WATER and SUBTERRANEAN_CHASM) - so all in all its six different sets of new creatures and plants, making the caverns a more hostile and difficult place to explore (admittedly the trees and grass don't always pop up where I wanted them to go but it was an interesting experiment nonetheless)This mod is mostly meant for fort mode - although for adventure mode players, some of the intelligent underground creatures are available for playing from fortress civs.Each layer has many predators, non-hostile creatures, and vermin - aside from that, all of them also have several rare but powerful "boss" type creatures, somewhat analogous to the Cave Dragons in vanilla. I've designed most of them, though some are just based off of common "tropes" like cave worms.The sets are as follows:- Layer 1 ChasmThe simplest layer - it contains stranger relatives of aboveground animals, adapted to life underground. From the small, pack-hunting Spike Rats, to the tough Stone Boars and the massive Undertyrants, danger here takes many shapes and sizes.- Layer 1 WaterAn underground woodland, full of towering fungus. Most of the living creatures here are ambulatory plant-life or fungal-based beings - the few unfortunate enough to die are converted into Moldspawn or Moldslaves by the Amanitarians.- Layer 2 ChasmSome of the deeper underground tunnels are the habitat of various types of insectoid beings. Few would head down there, fewer still live to tell the tale. The Hive Queens and Swarm Lords bide their time here, seeking to purge the caverns and eventually the surface world of all non-insectoid life.- Layer 2 WaterWhat little remains of once-sprawling underground empires can be found here, in the form of many unnaturally mutated zombies, howling spirits and feral skeletal beings - with several necrophagous beasts moving in, attracted by the scent of decay. The Lords of the Risen, extradimensional demigods, have turned these tunnels into their domain, warding off intruders with their undead minions.- Layer 3 ChasmThe lowest tunnels are inhabited by many lesser demons and their commanders. Most of those unfortunate enough to encounter them are captured and turned into slaves - even their souls are not safe from being forced to serve - whereas the particularly hated enemies of the demons, such as the dragons, are simply mutilated, driven insane, and left alive to wander the caverns for eternity.- Layer 3 WaterSomething stirs deep below the earth...An unspeakable yet sickly horror whose mere presence is enough to warp the caverns into an organic, diseased dreamscape. Its minions kidnap those who dwell in the surface world, using their victims as material for creating horrid aberrations of flesh.Now, I haven't included lists of the non-hostile creatures and vermin - you'll have to find out what they are and what they do for yourself!Big thanks to my girlfriend for the banner - she occasionally posts art on her instagram if any of you are interested.Download links ("packaged with DF versions" are not updated for now - waiting until a more stable version of 47 comes out): Stand-alone version - lacks the vanilla raw changes I made (rearranged some of the underground plants and trees) - you can install it by simple dropping the "raw" folder into your main DF folder.Some of the material, body plan and body detail files are shared with my main pack - you don't actually need those if you're using this alongside my main pack.Hope you guys enjoy it!