The Mantle (concept(?))

[careeoki]

The Mantle is something I first mentioned in #1463 , basically being a hell/underworld/fiery death pit area.

It is made up of huge, wide-open caverns. This is basically an inversion of regular caves (mostly small tunnels with some large caverns.)
Its stone block is a very tough "mantle" stone that you'll need a strong pick to break. To mine it at a reasonable speed, you'll want to incase mantle blocks in your tool for the damage boost.

There's two ways that this layer could work:

current implementation:
The mantle starts at -40000, which is also where normal caves now stop. It ends at -48250, leading into the dropoff.

alternative implementation (ARG's idea):
The mantle is a progression check/challenge from -15k to -20k (or wherever makes sense).
Instead of the mantle, -40k is a "cold core" layer, with similar open caverns but with a frozen theme.

I do think a cold core would be cool, and I have some ideas of what that could look like.

Mantle blockset

Mantle is a dark red stone with a cracked/scarred appearance, inspired by Komatiite (especially that first picture wikipedia has)

I found this stone to be very frustrating to work on, I want a dark red stone since that's what feels most thematically appropriate for a "planet's core" biome, but I feel no matter what I do, it's going to look like netherrack
I do think what I came up with is fun and unique, regardless of baseline similarities.

There's also the ash block, which is not exclusive to the mantle (I added it to the lower slopes of volcanoes.)
It's a block that I imagine could be used for a variety of different biomes, and more grey tones are always nice to have.

things i would like:

• Allow flipping SBBs upside-down when generating on ceilings #2474 so that i can have the stalagmites on the ceiling as well (without duplicating all the sbbs)
• I would love to have a giant lava pool at the bottom of the mantle, separating it and what's below. It would represent the "planet's" "core" and may provide an interesting challenge before being able to progress further
• if crystals become unhardcoded Turn the crystal generator into a configurable structure. #563 i would make some colors rarer/not appear at all

[Vinywar123]

Made a extra biome for the mantle if you want to use it

[Argmaster]

I think it looks like the magma caves. It has typical procedural content issue "I have already seen this". After seeing the screenshots, I would argue to make it a cold core, since it's just above great emptiness. We could make the hot layer higher, where it is separated from void, but still, reusing assets from lava caves seem lame to me :C

[careeoki]

A cold core does sound pretty cool... but I also want a hot layer as well, I think it being higher up like you said could work. something like this:

And yeah, I've really not put much time into the generation. I'm going to start making some unique SBBs to appear here, and try to make it as distinct from the lava caves as I can.

[du82]

I like it a lot! especially the new blocks! I think we need a lot more block textures and colors