My Superdungeon, Skull Mountain

Back in 1981 I decided to add a big dungeon to my AD&D 1e campaign. Originally started as almost-a-joke it persists 43 years further on. I have lost count of the number of PCs that have gone in as well as how many have never come out.

A Party at the entrance to Skull Mountain

I am not sure when the term ‘megadungeon’ became popular, but back then I just called it a dungeon until the players started calling it a super-dungeon, a term I still use. I had very clear ideas on three things - the second level, the most important level, and using a deep vertical cave leading to a lake. The rest was either sketched in or just made up when I got there.

It started out as 14 levels in what I now call ‘the Main Stack’ area and multiple more in the ‘Hidden Ways’ and ‘Shadow Lake’ area but there were always hints of a lot more. Exploration was a real commitments because of the surrounding terrain, called the Briars.

Stripped Down map. 1 hex = 1 mile. Between Esber (the closest settlement) and the Plateau outside the entrance the terrain rises over 6,000 feet.

The Low Briars (the yellow terrain) is hills with thick brush. The High Briars (the gray terrain) is very rough hills covered in sprawling briar thickets up to 12’ high. The main road is the only route with any certainty, the few trails are meandering mazes that often dead end. The is one known source of water on the road, a stream called the Rill, about 10 miles form the Plateau. There is virtually no game, the only inhabitants are trolls, giants spiders, the most desperate of renegades, small venomous spiders with a bite that can kill a grown man in an hour, and the insane.

Real delving didn’t get going until 1983 and by 1985 the central area had ballooned outward significantly and PCs had added 7 rooms to the dungeon (mainly little hidey-holes or equipment caches). and the Western Warrens had been founf. By 1988 a total of about 20 small areas and a small level had been added and major re-arrangements of some features had happened through magic - the Western Warrens were confirmed to go at least 35 miles. By 1995 another entire level had been added by a different PC, the the Eastern Caverns had been followed for over 20 miles, and the entrance to the Southern Catacombs had been found.

Also during that time another two levels were added by PCs (directly once, indirectly the other time), a major modification to the top of the mountain had occurred, associated areas up to 90 miles away had been discovered, and PCs had found, and fled, the City of Shadows and Darkness, resting in the Lake Village, and the underground canals had been discovered, some of them seeming to stretch for up to 80 miles, total.

By 2015 the Ocean Entrance had been found (if not opened) proving the eastern Caverns stretched at least 120 miles and a way through the Caverns of Slime had been opened, allowing access to what the PCs named the Hobgoblin Highway, a long series of tunnels that could theoretically allow trade with the nation south of the mountain range via underground routes. If you were bold.

In the last 10+ years players have added yet another level. The Monster Maze was found and cleared, reactivating the Atmosphere Generator for one of the moons. Likewise the Tomb of the Space Elves, the Midden, and many other areas were found and at least lightly explored.

Since at least 1985 an existing network of teleporters had been discovered, modified, and sometimes trapped and ultimately two other teleporter networks were added to the dungeon allowing quick access to and from areas as far away as (most extreme) one of the moons (although that voyage requires a lot of underwater swimming).

There are a surprising number of shocking normal permanent inhabitants of the dungeon, mainly in the Hidden Ways. These range from a retired adventurer and his family to a hidden LG Cathedral. more than one PC has a home or regular base tucked away in the same region, causes some explorer to find rather odd flayers pasted to the walls of certain spaces.

Ladies are half Price every Thursday!

Of course not all inhabitants are great fellows of a positive outlook. The Headsman and Executioner were major threats for a long time. The Grandfather of Assassins lived in the dungeon before his untimely demise (he was a very stabilizing influence nearby, he liked a quiet neighborhood), and of course there’ Rupert.

But no one talks about Rupert.

Based on my maps and notes about 40% of the entire complex is still totally unknown or just hinted at to the players. Of the 60% known less than 40% has been actively explored. Of the well-known areas a lot of it has modified by PC actions.

The size of the Skull Mountain dungeon and the sheer complexity of the interactions between the various inhabitants has led to a lot of table humor, with two of my favorites being,

”Once you’ve gotten down to the third level of Skull Mountain you’ve fought kobolds, skeletons, goblins, bandits, elementals, and a lesser Devil and you think ‘Ok, quite a spooky abandoned dungeon’. Then you find level 21 and it’s the middle of the Zoning meeting and you can sign up for the newsletter. You’re still gonna die, but there’s donuts and coffee in the back”

and

Player One: “Eventually we’re going to have to destroy the Grandfather of Assassins.” Player Two: “One of my characters can’t do that, they’re in the same HOA.”

I have had a few people ask me to publish Skull Mountain, but I don’t think I could. Perhaps the top three levels of the Main Stack, someday.

In the meantime, I plan to keep it going.