Modscraper Modscraper Minecraft
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The Lost Underground

Modpack

by Legundo

Can you survive and never see the sun?

Type

Modpack

CurseForge Downloads

5,081

CurseForge ID

1186101

Last Updated

Jul 26, 2026

Description

I Survived 100 Days in the lost underground, and now you can too!

This is my latest multiverse adventure, a world of clashing dinosaurs, radioactive abominations, and... Unicorns and Candy?!?! Don't even get me started on the Sculk too... This Caves Only world is a nail biting adventure from beginning to end... and it ends with a BANG.

PLEASE NOTE

Due to the way this world generates (by default with the Lithospherical world type) - certain Alex's Caves structures will not generate. This includes the Primordial Volcano, Candy Cavity witche's tower, and the Abyssal Caves biome entirely. Due to this, some Alex's Caves bosses will be unavailable.

This modpack works entirely on it's own, but to download my specific map from the video, support me on Patreon!
https://patreon.com/Legundo

 

This modpack is as featured in my Hardcore 100 Days video!

Compatibility

Mod Loaders

Forge

Game Versions

1.20.1

Recommended Gear

Affiliate

Hardware and extras that pair well with this modpack.

As an Amazon Associate I earn from qualifying purchases.

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Just Enough Items (JEI)

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View Items and Recipes

Mod 697,088,226
GeckoLib

GeckoLib

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Mod 474,228,372
Cloth Config API (Fabric/Forge/NeoForge)

Cloth Config API (Fabric/Forge/NeoForge)

Config Screen API for Minecraft

Mod 540,090,556
Architectury API

Architectury API

An intermediary api aimed to ease developing multiplatform mods.

Mod 441,044,058
Mouse Tweaks

Mouse Tweaks

Enhances inventory management by adding various functions to the mouse buttons.

Mod 531,744,358
AppleSkin

AppleSkin

Adds some useful information about food/hunger to the HUD

Mod 500,016,071
Balm

Balm

Abstraction Layer for Multi-Loader Mods

Mod 310,349,551
Bookshelf

Bookshelf

An open source library for other mods!

Mod 412,966,100
Curios API (Forge/NeoForge)

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A flexible and expandable accessory/equipment API for users and developers.

Mod 335,668,043
Controlling

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Adds a search bar to the Key-Bindings menu

Mod 430,137,975
Xaero's Minimap

Xaero's Minimap

Displays the nearby world terrain, players, mobs, entities in the corner of your screen. Lets you create waypoints which...

Mod 354,272,274
Clumps

Clumps

Clumps XP orbs together to reduce lag

Mod 407,195,925
Xaero's World Map

Xaero's World Map

Adds a fullscreen worldmap which shows you what you have explored in the world. Can work together with Xaero's Minimap.

Mod 309,914,383
Sophisticated Backpacks

Sophisticated Backpacks

Yet another backpack mod this time with backpack you can place in world, color in different color combinations, upgrade...

Mod 258,818,378
FerriteCore ((Neo)Forge)

FerriteCore ((Neo)Forge)

Memory usage optimizations

Mod 219,920,180
Puzzles Lib

Puzzles Lib

Why is it called Puzzles? That's the puzzle.

Mod 275,318,648
Cupboard

Cupboard

Cupboard provides code, frameworks, and utilities for minecraft mods

Mod 201,986,800
Searchables

Searchables

Searchables is a library mod that adds helper methods that allow for searching and filtering elements based on component...

Mod 211,500,339
Enchantment Descriptions

Enchantment Descriptions

Adds in-game descriptions for enchantments to tooltips.

Mod 324,555,819
Sophisticated Core

Sophisticated Core

Library mod for Sophisticated mods

Mod 222,525,322
Farmer's Delight

Farmer's Delight

A cozy expansion to farming and cooking!

Mod 254,910,540
Patchouli

Patchouli

Accessible, Data-Driven, Dependency-Free Documentation for Minecraft Modders and Pack Makers

Mod 329,492,054
Kotlin for Forge

Kotlin for Forge

Adds a Kotlin language loader and provides some optional utilities.

Mod 248,502,130
Nature's Compass

Nature's Compass

Nature's Compass is an item that allows you to locate biomes anywhere in the world.

Mod 321,471,700
Embeddium

Embeddium

A powerful, mod-friendly, FOSS client performance mod for NeoForge

Mod 184,964,675
Polymorph (Fabric/Forge/Quilt)

Polymorph (Fabric/Forge/Quilt)

No more recipe conflicts! Adds an option to choose the crafting result if more than one is available.

Mod 247,070,961
Framework

Framework

A common library powering all of MrCrayfish's Mods

Mod 136,434,801
Carry On

Carry On

Carry On allows you to pick up Tile Entities and Mobs and carry them around!

Mod 241,851,531
Create

Create

Aesthetic Technology that empowers the Player

Mod 235,005,162
Oculus

Oculus

Unofficial Fork of "Iris", made to work with FML

Mod 207,463,660
ShatterLib | OctoLib

ShatterLib | OctoLib

Collection of shared code for Shatterbyte mods

Mod 107,600,872
Citadel

Citadel

A Lightweight Library

Mod 224,249,400
Resourceful Config

Resourceful Config

Resourceful Config is a mod that allows for developers to make crossplatform configs

Mod 153,790,484
YUNG's API (Forge/NeoForge)

YUNG's API (Forge/NeoForge)

A library mod for YUNG's Minecraft mods

Mod 216,021,072
Packet Fixer

Packet Fixer

A simple mod to solve various problems with packets, NBTs and timeouts.

Mod 136,215,301
Alex's Mobs

Alex's Mobs

85+ New mobs with stylistic quality above the default game.

Mod 169,390,014
YUNG's Better Mineshafts (Forge/NeoForge)

YUNG's Better Mineshafts (Forge/NeoForge)

A long-awaited and much-needed abandoned mineshaft overhaul!

Mod 165,200,080
Artifacts

Artifacts

Adds various treasure items that can be found through exploration

Mod 155,769,315
Caelus API

Caelus API

A coremod and API to provide developers access to elytra flight mechanics through an entity attribute.

Mod 172,368,615
TerraBlender (Forge)

TerraBlender (Forge)

A library mod for adding biomes in a simple and compatible manner!

Mod 195,186,484
Server Performance - Smooth Chunk Save[Forge/Fabric]

Server Performance - Smooth Chunk Save[Forge/Fabric]

Enables lag-free continuous chunk saving, increasing server TPS

Mod 120,477,210
Configured

Configured

Automatic in-game configuration menus for every mod!

Mod 126,773,005
NetherPortalFix

NetherPortalFix

Ensures correct destinations when traveling back and forth through Nether Portals in Multiplayer.

Mod 184,850,973
Just Enough Resources (JER)

Just Enough Resources (JER)

A JEI addon that adds mob drops, ore gen, ..

Mod 247,171,608
fix GPU memory leak[Forge/Fabric]

fix GPU memory leak[Forge/Fabric]

A mod that fixes memory leaks on the client

Mod 103,759,462
YUNG's Better Nether Fortresses (Forge/NeoForge)

YUNG's Better Nether Fortresses (Forge/NeoForge)

A complete redesign of Minecraft's Nether fortresses!

Mod 105,864,519
Necronomicon API

Necronomicon API

A personal utility library, making development in both platforms easier.

Mod 88,926,458
Just Enough Professions (JEP)

Just Enough Professions (JEP)

A JEI addon that adds profession workstations

Mod 112,853,286
YUNG's Better Strongholds (Forge/NeoForge)

YUNG's Better Strongholds (Forge/NeoForge)

A complete redesign of Minecraft's strongholds

Mod 125,252,224
YUNG's Better Ocean Monuments (Forge/NeoForge)

YUNG's Better Ocean Monuments (Forge/NeoForge)

A complete redesign of Minecraft's ocean monuments!

Mod 106,684,021
Loot Integrations

Loot Integrations

Allows loot from loottables to be integrated into other lootables, inherently adds better dungeon loot to a few structur...

Mod 79,544,713
YUNG's Better End Island (Forge/NeoForge)

YUNG's Better End Island (Forge/NeoForge)

An overhaul of the main End Island where the dragon fight takes place!

Mod 89,247,324
Relics

Relics

Just a mod about useful items with unique mechanics :3

Mod 64,598,494
Elytra Slot

Elytra Slot

Adds curio support to the elytra so you can fly and wear chest armor at the same time. Formerly known as Curious Elytra.

Mod 131,686,130
MVS - Moog's Voyager Structures

MVS - Moog's Voyager Structures

160+ structures made with vanilla blocks and entities bringing life to your world! Discover loot, enemies, & villagers a...

Mod 70,176,120
Chunk Sending[Forge/Fabric]

Chunk Sending[Forge/Fabric]

Optimizes chunk packet delivery

Mod 70,479,263
YUNG's Better Witch Huts (Forge/NeoForge)

YUNG's Better Witch Huts (Forge/NeoForge)

Adds overhauled witch huts to swamps!

Mod 84,285,390
YUNG's Better Jungle Temples (Forge/NeoForge)

YUNG's Better Jungle Temples (Forge/NeoForge)

A complete redesign of Minecraft's jungle temples!

Mod 79,866,425
Creeper Overhaul

Creeper Overhaul

A mod which overhauls the vanilla creepers!

Mod 95,183,428
Goblin Traders

Goblin Traders

Adds goblins that you can find underground with unique and useful trades!

Mod 88,008,705
YUNG's Better Desert Temples (Forge/NeoForge)

YUNG's Better Desert Temples (Forge/NeoForge)

A complete redesign of Minecraft's desert temples!

Mod 83,226,408
Easy Magic

Easy Magic

Enchanting tables as they always should have been! Items stay after closing, and easy re-rolls.

Mod 88,171,652
Client Crafting

Client Crafting

Clientside crafting without network delay

Mod 49,384,443
Easy Anvils

Easy Anvils

Overhauled anvils with stored items, fairer costs, and no more frustrating repair penalties.

Mod 81,371,716
Repurposed Structures (Neoforge/Forge)

Repurposed Structures (Neoforge/Forge)

Adds more variations of vanilla structures and features such as a Jungle Fortress!

Mod 96,883,041
YUNG's Bridges (Forge/NeoForge)

YUNG's Bridges (Forge/NeoForge)

Adds beautiful naturally generated bridges throughout the world

Mod 83,046,618
Cobweb

Cobweb

Crystal Nest API

Mod 37,696,892
Chloride (Embeddium++/Sodium++)

Chloride (Embeddium++/Sodium++)

Gives to Sodium (and Embeddium for 1.20.1) additional Performance and Quality features for a tasteful experience

Mod 55,301,979
CullLessLeaves Reforged (Unofficial)

CullLessLeaves Reforged (Unofficial)

Gives you a 9% fps improvement for leaves rendering

Mod 40,208,225
YUNG's Extras (Forge/NeoForge)

YUNG's Extras (Forge/NeoForge)

Extra structures, features, and vanilla+ content suitable for any modpack

Mod 78,742,193
Alex's Delight

Alex's Delight

Adds compatibility between Alex's Mobs and Farmer's Delight

Mod 47,069,083
Boat Break Fix [Neo/Forge/Fabric/Quilt]

Boat Break Fix [Neo/Forge/Fabric/Quilt]

Fixes a breaking bug with boats and increases performance.

Mod 46,452,618
Reliquified Artifacts

Reliquified Artifacts

Compatibility addon between Relics and Artifacts

Mod 27,416,882
Trading Post

Trading Post

Rule the village! Trade with every villager at once!

Mod 66,614,008
MonoLib

MonoLib

A non-invasive library mod for Fabric, Forge, and NeoForge.

Mod 31,367,073
Alex's Caves

Alex's Caves

Explore five new rare cave biomes hidden under the surface of the Overworld...

Mod 43,703,615
Just Enough Archaeology

Just Enough Archaeology

JEI and EMI Archaeology addon

Mod 31,133,439
Nether's Delight

Nether's Delight

Nether addon for Farmer's Delight

Mod 79,364,754
Yung Structures Addon for Loot Integrations

Yung Structures Addon for Loot Integrations

Adds better loot to yung mods structures, an addon to the lootintegrations mod

Mod 23,465,933
Starlight (Forge)

Starlight (Forge)

Rewrites the light engine to fix lighting performance and lighting errors

Mod 58,881,151
YUNG's Cave Biomes (Forge/NeoForge)

YUNG's Cave Biomes (Forge/NeoForge)

Adds new vanilla+ cave biomes and underground content!

Mod 24,806,325
Friends&Foes (Forge/NeoForge)

Friends&Foes (Forge/NeoForge)

Adds outvoted and forgotten mobs from the mob vote, expanding on their original concepts and adding new vanilla-like fea...

Mod 45,686,087
Illager Invasion

Illager Invasion

The illagers are back! Be ready to fight new foes. A port of Illager Expansion.

Mod 39,432,734
Incendium

Incendium

New biomes and structures with the vanilla blocks! (1.18+)

Mod 44,951,071
Galosphere

Galosphere

This mod aims to improve the underground by adding new cave biomes, mobs, ores... etc

Mod 38,986,580
Bartering Station

Bartering Station

Still running around bartering manually? Let's put those lazy piglins to work instead!

Mod 47,264,829
YUNG's Menu Tweaks (Forge/NeoForge)

YUNG's Menu Tweaks (Forge/NeoForge)

A small, lightweight mod that makes browsing menus a lot easier

Mod 25,513,183
DEUF - Duplicate Entity UUID Fix

DEUF - Duplicate Entity UUID Fix

Changes UUIDs of loaded Entities in case their UUIDs are already assigned (and removes log spam).

Mod 33,016,462
Bygone Nether

Bygone Nether

Adds new biome-specific structures and mobs to the nether dimension

Mod 52,140,428
Create Stuff 'N Additions

Create Stuff 'N Additions

🧲 Dominate your environment with Create technology

Mod 36,289,812
Radiant Gear (Fabric/Forge/Quilt)

Radiant Gear (Fabric/Forge/Quilt)

A compatibility bridge between Curios API or Trinkets API and dynamic light mods such as Dynamic Lights and Lucent.

Mod 22,766,549
Harvest with ease

Harvest with ease

Don't break crops, right click them!

Mod 35,171,185
DnT Ancient City Overhaul

DnT Ancient City Overhaul

Standalone Splinter version of Dungeons and Taverns Ancient City Overhaul

Mod 14,333,002
Stay True

Stay True

Staying True to The Original Textures.

Texture Pack 46,672,104
Complementary Shaders - Reimagined

Complementary Shaders - Reimagined

Preserving the elements of Minecraft with exceptional quality, detail, and performance.

Shader 237,782,141
Underground Villages

Underground Villages

Adds underground villages to your world

Mod 15,811,968
More Mob Variants

More Mob Variants

Adds new variants to existing mobs.

Mod 29,929,818
Dynamic Lights

Dynamic Lights

portable and moving lightsources

Mod 35,825,822
Noisium (archived)

Noisium (archived)

Optimises worldgen performance for a better gameplay experience.

Mod 68,583,803
Enemy Expansion

Enemy Expansion

Adding variety to combat encounters in Minecraft!

Mod 8,083,103
Adaptive Performance Tweaks: Core

Adaptive Performance Tweaks: Core

The core is required for all adaptive performance tweaks modules and provides a shared API, monitoring functionally, eve...

Mod 12,695,640
Adaptive Performance Tweaks: Items

Adaptive Performance Tweaks: Items

Item clustering (fallen blocks, experience orbs, ...) and garbage cleanup.

Mod 10,379,505
Curious Lanterns

Curious Lanterns

Provides a hip slot for your illuminated mining needs! Requires a dynamic lights mod.

Mod 13,133,892
Relics: Alex's Mobs Compat

Relics: Alex's Mobs Compat

Compatibility addon between Relics and Alex's Mobs

Mod 9,820,425
Miner's Delight +

Miner's Delight +

Farmer's Delight add-on for miners

Mod 17,162,272
Villagers Sell Animals [NoCube's Mods]

Villagers Sell Animals [NoCube's Mods]

Adds new villager deals. Makes animals renewable. Vanilla-style

Mod 8,086,875
Relics: Alex's Caves Compat

Relics: Alex's Caves Compat

Compatibility addon between Relics and Alex's Caves

Mod 7,453,779
Alex's Caves Delight

Alex's Caves Delight

Adds compatibility between Alex's Caves and Farmer's Delight. Vanilla style.

Mod 3,613,299
Alex's Caves: Stuff & Torpedoes

Alex's Caves: Stuff & Torpedoes

💥Adds torpedoes and equipment related to Alex's Caves

Mod 3,944,399
TACT - Tiny Alex's Caves Tweaks

TACT - Tiny Alex's Caves Tweaks

Tiny Alex's Caves Tweaks to make the mod a bit better

Mod 13,198,099
More Minecarts and Rails

More Minecarts and Rails

Expands minecarts and rails to provide intuitive, viable trasportation, automation and utility solutions.

Mod 9,876,267
Create: Design n' Decor

Create: Design n' Decor

A Create addon focused on QOL decoration features that expand on the base decoration ability of Create whilst focusing o...

Mod 13,907,977
ATi Structures

ATi Structures

A Pack adding a variety of structures found in the overworld

Mod 7,459,016
DnT Stronghold Overhaul

DnT Stronghold Overhaul

This is the Standalone split off version from Dungeons and Taverns Stronghold Rework. It adds 417 Rooms, Unique Strongho...

Mod 4,401,878
Adaptive Performance Tweaks: Spawn

Adaptive Performance Tweaks: Spawn

Optimization for monster spawn events and spawner.

Mod 3,550,420
Large Meals (An Add-on for Farmer's Delight)

Large Meals (An Add-on for Farmer's Delight)

A Farmer's Delight addon that adds new and creative recipes to the game.

Mod 8,187,780
Deep Dark: Regrowth

Deep Dark: Regrowth

A big horror expansion for the Deep Dark with new biomes and mobs.

Mod 4,706,037
Adaptive Performance Tweaks: Player Login Optimization and Protection

Adaptive Performance Tweaks: Player Login Optimization and Protection

Protects players during login and provides a special "easy" mode for less experience and child players.

Mod 4,010,931
Adaptive Performance Tweaks: Gamerules

Adaptive Performance Tweaks: Gamerules

Automatically adjust the random tick speed, entity cramming, raids, patrol, trader and insomnia based on the current ser...

Mod 4,038,372
Adaptive Performance Tweaks (Bundle)

Adaptive Performance Tweaks (Bundle)

The Adaptive Performance Tweaks mod automatically adjust specific settings on the server to allow a better TPS/FPS.

Mod 4,664,415
ReForgedPlay [replay mod on (neo)forge]

ReForgedPlay [replay mod on (neo)forge]

Replay mod port to (neo)forge! Record your adventures in minecraft

Mod 2,482,781
Stackable Stew and Soup

Stackable Stew and Soup

Now you can stack the default stews and soups up to a maximum of 8 (configurable)

Mod 6,458,702
WI Zoom

WI Zoom

The zoom from the Wurst Client as a standalone mod.

Mod 18,677,390
Create: Enchantable Machinery

Create: Enchantable Machinery

This mod allows you to apply some vanilla enchantment to Create blocks.

Mod 5,721,152
Default World Type [Forge]

Default World Type [Forge]

Change the default world type for creating a new world

Mod 11,376,538
Mineral Delight

Mineral Delight

Crush, Cook and Eat Ores, Gems, and Crystals!

Mod 1,053,027
Create: Dynamic Village

Create: Dynamic Village

Expansion that adds a fully-featured host of Create-mod village professions.

Mod 7,513,569
DespawnTweaker

DespawnTweaker

better Let Me Despawn optimization | Don't allow mobs from spawners to despawn

Mod 16,388,851
NoFog

NoFog

A highly configurable client-side Fabric, Forge(<=1.20.1) and NeoForge(1.20.2+) mod that removes all fog

Mod 8,141,533
Illager Additions

Illager Additions

This is a mod about illager content

Mod 2,162,215
Create: Protection Pixel

Create: Protection Pixel

A fancy armor mod with steampunk/create style

Mod 2,375,982
Alex's Mobs Interaction

Alex's Mobs Interaction

An addon that adds tons of new features specifically for the mod Alex's Mobs

Mod 1,377,508
Only Hammers And Excavators

Only Hammers And Excavators

A simple mod that adds various type of hammers & excavators, that mine 3x1 area

Mod 1,841,490
Piercing Paxels ⚒️

Piercing Paxels ⚒️

Dynamic Upgradable Multi-tools!

Mod 1,605,213
Better Brightness Slider

Better Brightness Slider

Drag the brightness-/gamma-slider to higher and lower values than default

Mod 2,863,466
Adaptive Performance Tweaks: Mods

Adaptive Performance Tweaks: Mods

Automatic and realtime server bundling (one mod pack for client/server) and mod clean up for better performance and less...

Mod 2,691,188
project-869951

project-869951

Books & Ladders Wood Variants!~

Mod 561,772
Ecospherical Expansion

Ecospherical Expansion

Overhauled generation to the biomes of the Overworld.

Mod 928,833
Phantom Loader

Phantom Loader

Phantom Loader is a library that automates part of the process of creating Minecraft mods for multiple mod loaders by ge...

Mod 1,574,316
Buried Wrecks

Buried Wrecks

A mod that adds buried shipwrecks to the underground

Mod 225,053
HRB's Drills

HRB's Drills

A vehicle to make mining a better experience.

Mod 123,485
Cave Spelunking[Forge/Fabric]

Cave Spelunking[Forge/Fabric]

Prevents ores from spawning not exposed to air/fluids/other ore blocks

Mod 1,520,422
Miner Villager

Miner Villager

A new entity for the Mineshafts!

Mod 744,887
Modifiers

Modifiers

Mod that adds Terraria-style modifiers to equipment.

Mod 2,305,782
Spider Caves

Spider Caves

Adds a spider cave biome and a spider armor

Mod 1,078,232
Azarbeat's Edible Monsters (Eat Zombies, Spiders, and much more!)

Azarbeat's Edible Monsters (Eat Zombies, Spiders, and much more!)

You can eat mobs now!! Enjoy the meal and have a nice day!!

Mod 68,813
project-1091132

project-1091132

This mod expand caves by adding a ton of stuff to make caves better like new biomes and mobs, it also adds new decorati...

Mod 62,663
project-1084974

project-1084974

A tiny performance mod, decreasing the rate some Create components tick at

Mod 104,256
Glowroot Caves

Glowroot Caves

A cave-biome mod based on the glow squid with new mobs, structures, and mechanics.

Mod 130,038
project-1078171

project-1078171

Adds to cave biomes dishes and food. Vanilla style.

Mod 50,964
What is 'Stone'? (Colorful Caves)

What is 'Stone'? (Colorful Caves)

Let's add a bit of spice to the existing caves, vanilla style!

Mod 42,080
Glowroots Two Electric Boogaloo

Glowroots Two Electric Boogaloo

Adds a new biome the glowroot Cavern

Mod 6,632
Cave Maps (Better Nether Map Port)

Cave Maps (Better Nether Map Port)

Configurable Maps for Caves and Cave Dimensions

Mod 43,052
WHAT THE GECKO

WHAT THE GECKO

Yes that's what you heard, here you can found geckos,reptiles, lizards,Tuataras and amphibians

Mod 178,717
[BMS-SGA] "New" Sculk Expension Cave+

[BMS-SGA] "New" Sculk Expension Cave+

Rediscover the Deep Dark of Minecraft !

Mod 16,995

External Resources