Those Under the Mountain ALPHA

If you haven't checked out the FREE quickstart to Those Under the Mountain, do that before going any further here: Quickstart

TUM Alpha

This project page is for early access of the (kinda)-full in-development rules for Those Under the Mountain. This is not a polished document, and is not formatted nicely, nor is it necessarily filled with art. This is a living development build that will change dramatically over the next year or two before full release. There are contradictions, ambiguity, and broken elements. What it does have, is a janky, but more complete version of TUM for those who wish to support ongoing development, and it will only improve and expand in the coming months.

Your purchase of this early access version will grant you the full digital PDF version on release, and an optional "Founding Member" credit (if desired) in the game. 

Purchase of the alpha here will NOT transfer over to crowdfunding when the campaign begins later this year, so if you only have $20 to spend, I ask that you wait for the crowdfunding launch. Thanks :)

As of 6/14/26, the game is at 75% content complete, thereabouts.

This means that the rules, systems, and play-focused elements of the game are around three quarters complete. This is not counting formatting, many additional tables, or art, as most of that will be tackled during the next development phase.

Dates of note:

Tentative Crowdfunding campagin: 8/20/26

As development continues, I'll be releasing somewhat regular builds, something like once a month. ~ish.

So, what's in here? Quite a bit.

This document contains the following in addition to all the great content available in the Quickstart:

• Expanded skills, as well as new skills including Leatherworking, Glassworking, Bowyery, Lore, Siegedwarfship, Piloting, and Beekeeping.
• Feats galore for customization, special abilities, etc.
• Magical skills such as Arcana, Runesmithing, and Alchemy.
• Expanded procedural tables
• Expanded mining
• Lore about the exotic materials, metals, and dangers of Carrion
• Expanded ancestries, including "Heritage" sub-ancestries for each one.
• More equipment, vehicles, siege engines, and more.
• Scenario prompts to inspire your fortresses. (like embarking in a volcano!)
• Ancient Horror generation tables
• Crazy worldgen tables 
• & more

What's currenly broken or unfinished? Well, here's the big stuff.

• Feats are incomplete and need rebalancing
• Some skills are currently still being improved and developed
• Bestiary and "making a monster" are very barebones atm
• Gamemastering section is under construction
• Economy needs rebalancing
• Missing chapter on solo play
• Missing lots of spells and magic
• Ancestry and heritage balancing, finishing
• Tons of small tweaks and additions
• Art and layout.

I'm making this available for earlybirds who love the quickstart and want more. I want you all to be a part of it.

Join the Fortress. Dig deep.

Come say hi! https://www.reddit.com/r/TUMrpg/

And follow my socials for updates as development continues: