Mantle Caves

Mantle Caves is an underground cave biome added by Terralith. It is a dark cavern biome built from blackstone, basalt and magma, lit mainly by lava. It is tagged as a cave and as an overworld biome, and strongholds are biased toward it. Because it sits deep in the cave layer, a player who digs for ores or explores caves will reach it regularly.

Description

Mantle Caves has black fog and a black sky, so the only light comes from the player's own sources and from lava. Water in the biome is a deep blue (#1b46d0), and its underwater fog is a dark navy (#050533). The ambient sound is the vanilla cave sound, and falling lava particles drip from ceilings at a low rate.

The floor is mostly blackstone, with patches of smooth basalt and magma blocks. These strips run through the cavern in bands. The ceilings produce lava drips, falling columns of lava that hang from blackstone and magma block surfaces. Lava springs also appear in the rock, so lava can spread across the cave floor from a single source.

Vegetation is sparse and comes from the plains feature set. Grass, tall grass, flowers, brown and red mushrooms, sugar cane, pumpkins and glow lichen grow where the ground allows, and plains-style trees appear in open areas.

Generation

Mantle Caves is placed in the underground cave layer by the cave and canyon carvers. In the live world it makes up 1.33% of the cave layer at y = -30. Its climate is warm (temperature 2) with no downfall and rain precipitation. It does not appear at the surface, so it is reached only by digging or by carving through rock.

Strongholds use the stronghold_biased_to biome tag, which makes them prefer generating near this biome.

Features

The biome uses the vanilla deep-overworld ore set: coal, iron, gold, redstone, diamond, lapis and copper, plus underwater magma, and sand, clay and gravel disks. Several ore placements are added by other mods in the pack:

• Infected deepslate diamond ore and infected diamond ore from Born in Chaos, and a black argillite placement from the same mod.
• Sulfur ore, salt disc and sulfur regeneration placements from Butchery.
• A mithril ore placement from Iron's Spells 'n Spellbooks.

Terralith adds its own cave features. Blackstone strips, magma strips and basalt strips are placed as patches of stone across the floor. The lava drips are spring features that sit on blackstone and magma block surfaces. Vanilla monster rooms and amethyst geodes can also appear in the same cave areas.

Mobs and structures

Mantle Caves has a very large monster list, with dozens of entries. Vanilla spiders, skeletons, zombies, creepers, slimes and endermen share the top weights with several Fear Nightfall mobs, including the Necromancer, the Dread Hound, the Mr. Pumpkin and Mrs Pumpkin variants and the Spiders Mother. The ambient spawns are bats and Coal Golems from Golem Overhaul. The underground water spawns are glow squids and Corpse Fish. The table below lists every spawn with its weight.

The biome can generate over a hundred structures. Many are horror structures from pack mods, such as the Graveyard crypt, the Born in Chaos firewell, gallows and dead oak trees, and the Nova Structures remnants. Vanilla mineshafts also appear. The generated table below lists the full set.

Monster

Ambient

Underground Water Creature

Water Creature

Water Ambient

Structures (103)

Mineshaft, Stronghold, Trial Chambers, Shrine Combat Tier 1, Shrine Combat Tier 2, Shrine Combat Tier 3, Shrine Combat Tier 4, Shrine Combat Tier 5, Shrine Tower, Crypt, Bunker, Ruin Town, Wild Ruin, Firewell, Campsite, Fire Camp, Horse Campsite, Mine With Campsite, Barn, Duck, Haystack, Horse Pen, Shed, Wheat Grain Bin, Windmill, Wooden Wheat Farm, Floating Islands, Large Floating Island, Azelea House, Deepslate House, Diorite And Deepslate House, House, Lil House, Tall House, Warped House, Small Oak Lantern, Blue Stall, Cart, Cartographer Tower, Large Cart 1, Large Cart 2, Orange Stall, Pink Stall, Red Stall, Castle Ruins, Crystal, Log Ruin, Ruined Beacon, Small Ruin, Statue Ruins, Stone Pillars, Arena, Calcite House, Castle Ruin, Castle Tower, Diorite House, Large Tower, Nether Portal, Small Deepslate House, Small Oak House, Small Tower, White House, Leaf Hollow, Small Pond, Tree 1, Tree 2, Tree 3, Tree 4, Tree 5, Tree 6, Tree 7, Tree 8, Volcano, Diorite Tower, Large Warped Tower, Dead Tree Oak, Tree Monument, Bench, Cathedral, Gallows, Lamp Chest, Mushroom Pond, Paths, Pile, Railway, Small Oak Pond, Sunzi Gate, Villager Statue, Rare Well, Small Copper Well, Small Tower Well, Small Well, Stone Fountain, Well, Remnant Big Remnant 2, Remnant Big Remnant 3, Remnant Big Remnant, Remnant Bridge Remnant, Remnant Medium Remnant 2, Remnant Medium Remnant, Remnant Miner Hut, Remnant School Remnant, Road Sign

Tips

• Carry light. The fog and sky are black, so visibility is limited to a few blocks and a dark corridor can hide a mob.
• Watch the ceiling. Lava drips fall from blackstone and magma surfaces and can set a player on fire.
• Avoid standing on magma blocks. They damage entities that stand on them, and magma strips cover parts of the floor.
• Check for lava springs before crossing an open floor, since a spring can flood a low area with lava.
• Expect groups. The monster list is large, so fight near a wall or at a corridor mouth where only one or two enemies can reach you at a time.