
The Underworld Mod
I don't know my version or loader





The Underworld Mod is a mod that revolves around a new dungeon made out of new blocks and containing new challenges inside. The dungeon is also the only place you cant find most things added by the mod, including special swords with effects and decorative items.
What does it add?
The Underworld Mod provides the player with a brand new challenge to take on and a journey never before explored. The rewards for managing to survive the Underworld Chambers include, but are not limited to:
Swords
The Starter Sword, a basic sword, about a strong as Netherite, that is easily acquirable once arriving at the chambers, its main purpose is to help the players who don't have enough resources have a chance.
The Knife, a small dagger that deals few damage, but compensates with its amazing attack speed, that evens out the damage.
The Blood Dagger, a blade that gives 10 seconds of the Bleeding effect to whatever entity is hit with it, the bleeding effect deals damage to the entity that has it with time.
The Ice Blade, a sword that stuns whatever it hits, giving it the Freezing effect, and making it unable to move, to break or place blocks, and to deal melee damage.
The Advanced Sword, a slightly better version of the Starter Sword that is balanced in attack speed and damage, but has no special effects.
The Healing Brand, a sword that gives HP to the player whenever it hits an entity with it, and if the entity has more max health than the player, the player gains the entity's max health when hitting it.
The Heavy Mallet, a weapon that has very low attack speed, but makes up for it with an extremely high damage that could kill players in one critical hit.
The Lightning, an electrical sword that strikes a lightningbolt on whatever entity it hits.

Shields
The Flaming Hielaman, a shield that sets whatever entity is blocked by it on fire for 15 seconds.

What is the plan for the future?
I plan to add even more swords with effects, and make each sword be bounded to a new boss. For example, a new blood boss mob that drops the Blood Dagger, or a new ice boss that drops the Ice Blade. They could spawn as specific rooms in the dungeon and have its own bigger room.
- Edition: Minecraft Java
- File type: .jar
- Minecraft versions listed: 1.21.4, 1.21.5, 1.21.6
- How to install: Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. → Download the .jar. → Put it in the .minecraft/mods folder and launch that loader profile.
- Where to get it: Opens on Modrinth — not every file is mirrored on our own servers.
Install steps are the general flow for this file type — How to install Minecraft Java mods & modpacks walks through it step by step.
- Ships as THE_UNDERWORLD_MOD.jar — drop this file into the mods folder
- Download size: 1.9 MB
- Download link checked 31 Aug 2026 — working
These come from our own check of the pack file, not from the source page.