update readme. There's always *something* you overlook when making a major release

* bring in the art assets from ClockGen's "better_caves_modpack" under CC BY 4.0,, code written from scratch.

* update mapgen_helper

* import ClockGen's giant mushroom schematics, make them and giant ferns growable

* add giant jungle mushroom, rough out actual cavern layer code framework

* fungal ceiling decorations

* decorate fungal floor a bit

* update mapgen_helper

* update primordial mushroom schematic placement to ensure it fits

* add giant mycelium fungoidal structure

* add giant mycelium to mapgen

* fix settings for giant mycelium

* make mycelium grow when players aren't present

* allow mycelium growth to pause when it hits unloaded areas

* add a use for giant mycelium

* make giant mushrooms edible, make jungle trees growable

* rough out the jungle biome

* Make a spectrum of jungle growth

* optimize pngs, add is_ground_content to everything

* use custom is_ground_content method

* fix a crash with veinstone, and simplify nvals_cave lookup now that overgen covers the same area

* more fixes for overgen support

* remove unintentional airspace from underside of slade

* fix for overgen crash in level 2

* primordial column material, add sealed shafts to underworld

* add seal block

* Set up puzzle seals to be able to dig a staircase shaft through the slade layer. TODO: the puzzle to guard the trigger.

* puzzle seals now fully functional. Need to add clues for decoding the keys next.

* add a small bit of anti-griefing - the seal breach bell only tolls globally 13 times per activation

* add flowers to the underworld warrior bones

* switch to a different key bell

* fancy up the puzzle seal temples with some custom blocks, add sub-slade grid passages

* add a clue to the seal formspec

* tweak background of inscription 2 so it's less obviously a copy of the background for inscription 1

* switch to compositing to save a few bytes

* fancy up the seal's upper surface with inscriptions to make the formspec feel consistent

* puzzle particle, bones were only spawning on top of structures

* fix ice/oil on level 3, tweak some loot probabilities

* add trail mod support

* remove deprecated files

* boost default plant growth delay, add growing selection boxes

* update map colours

* add named waypoints to the underworld

* try a more efficient way of changing the interiors of columns

* polishing up the Primordial layer

* update guide with some Primordial teasers

* updated magma sea screenshot

* update mapgen_helper and subterrane

* reduce density of megaflora a bit - was too hard to walk through

* spreading_dirt_type depends on light, create my own ABM instead

* add names to the glowing pits and some of the ruins

* separate setting for ruin markers

* record identity of slade-breachers

* make mycelia climbable

* update subterrane

* change surface tunnel detection to allow above-ground stalactites and stalagmites

* add rare thicker Goblin Caps, suitable for use as huts.

* better goblin cap schematics

* update colours

* make it slightly harder to dig down through amethyst sheathing of pits

* fixing up fungus light sensitivity, tree growth code

* fix a few minor bugs

* update deprecated functions

* add various eating sounds

* make mapping kit requirement more flexible

* update spindlestem growth code, remove deprecated functions

* fix leftover undefined variable

* add fireflies to primordial, spread out the post-mapgen node timer for plant matter a bit more.

* fix bones formspec

* add lbm to upgrade old bones

* fix slade undiggability

* make torchspines smokey and manually lightable

* fix drop definitions

* generate dry stalactites in near-surface caverns.

* caverns become far too smokey, alas

* add pitter patter of spore tree spores, alternate paper recipe

* new mapgen_helper metrics

* add smokey back to torchspine now that it can be dialed down a bit

* replace glowstone texture with a new animated one

* switch from ABM to node timer for mapgen mycelium growth

* make mapgen mycelium timer delay configurable

* improve the efficiency of giant mycelium growth using flat node array, fewer dereferences

* remove the smoke from torchspines again - it doesn't dissipate that deep underground

* give slade a more muted, gloomy hue to differentiate it from nether stone

* update screenshots with new slade colors

* update mapgen_helper

README.md

@@ -16,6 +16,8 @@ Below the Sunless Sea are seas of a more dangerous sort: lakes of oil and the ma
 
 At the very foundation of the world lies an ancient impenetrable realm. There are signs that life once existed here but it is now long gone. Its dead hollows rest on a layer of Slade, a dense material impervious to conventional mining efforts.
 
+Unconventional methods of penetrating the Slade do exist, however. And should it be breached, the exotic Primordial cavern layer can be found beneath.
+
 ## Other Features
 
 The giant caverns generated by this mod differ slightly from the default giant caverns found in some mapgens, they use an additional source of noise to generate more ledges and horizontal floors. They also contain stalactites and stalagmites of various sizes - from single-node spikes decorating the default twisty tunnels to mountainous behemoths in the main caverns that can reach tens of meters in diameter and hundreds of meters in height.
@@ -37,3 +39,5 @@ The "[doc](https://forum.minetest.net/viewtopic.php?f=9&t=15912&p=240152)" mod i
 "[ropes](https://github.com/minetest-mods/ropes)" are very useful for navigating some of the large open spaces this mod provides.
 
 "[radiant damage](https://github.com/FaceDeer/radiant_damage)" greatly increases the danger of the Magma Sea if heat radiance is enabled, as well as several of the rare crystals in the deeper layers that emit Mese radiation if that damage type is enabled.
+
+Adding "[named_waypoints](https://github.com/FaceDeer/named_waypoints)" and "[namegen](https://github.com/FaceDeer/namegen)" will provide some landmarks in the Underworld that a player can use to navigate by.