D&D 5e: The Vault of Eternity

“The Vault of Eternity” is my latest project. Because this deals with the problems (and successes!) of running Out of the Abyss, please be aware that here there be spoilers. For those of you who’ve DM’d for the Rage of Demons story arc (and specifically for Out of the Abyss), one of the most common complaints I’ve seen is with the random encounters; no one seems happy with them, though the problems are wide-ranging and sometimes contradictory.(By the way, this is not intended to be a critique of Out of the Abyss, but just an expression of what was being juggled in my head as I sought to fill this particular gap!)

Among the problems players and DMs have mentioned:

1.      Too much bookkeeping:
If you follow the prescribed random tables exactly, you end up with the possibility of something like 160 encounters while traveling between places in the Underdark. Even if 75% of these are non-combat, that’s still a significant amount of dice rolling, stat tracking, and game time.

2.      Not enough variety:

After rolling on these same tables since level 1, the party will be fighting the same random encounters at level 10. This seems monstrously monotonous (regardless of any balance issues).

3.      Too many NPCs:

The Expeditionary Force the PCs lead back into the Underdark has very little functionality except as cannon-fodder and the creation of a second set of encounter tables. Without a set of mob-vs-mob rules, it becomes cumbersome at best to run these as written.

There are many, many bloggers and posters who have addressed these issues with novel

and often innovative solutions to the above issues, and I won’t attempt to summarize their findings here. The main point is that all of these problems become nearly insurmountable at a very specific point in the adventure: when the party is on their way to the library of Gravenhollow.


Though the module’s organization is a bit wonky as to where the information appears, there is a clear directive that PCs should be tenth level before they arrive at Gravenhollow. Even with an abundance of experience-yielding encounters and a few milestone level-ups, my players were only approaching ninth level when they were ready to start looking for the library. My players had already dealt with the major problems of each of the Underdark settlements that they were aware of (except Menzoberranzan, which they’ve been heavily disincentivized away from because of their party composition and backgrounds). They had beaten mini-bosses and fought through almost all of the random encounters at least once, and yet they were nowhere near where they needed to be, power-wise, to tackle the next leg of the campaign.
This is where the Vault comes in.

I needed the PCs to have a legitimate break from “The Demon Lords are everywhere!” without having a  completely unconnected side-quest. After all, the urgency of the campaign is part of its charm. Personally, I think that a few surface quests—included in Out of the Abyss—would have potentially filled this void. Unfortunately, my party consists almost entirely of Underdark races who have few ties to the surface, and after “escaping the Underdark” they were mostly adrift—they needed an excuse to return to it.
So what does “The Vault of Eternity” do?

1.      It provides an even more urgent reason to engage it than the main campaign does: a few friends are kidnapped after an earthquake; an investigation separates the party from their other friends but offers them an opportunity to pursue their friends’ kidnappers).

2.      It has the flavor of the Rage of Demons storyline: there are demons and cultists loose in the dungeon the PCs find themselves in. They’re connected to Orcus (and therefore, it feels like another in a long line of demon-lord-led-groups just as the PCs have found in each major settlement along the way).

3.      It is a traditional dungeon crawl: forty-some chambers, each self-contained, offers a traditional dungeon exploration experience within the sandbox of Out of the Abyss.

4.      It offers treasure and twists: a plethora of unique—named—magic items can be found throughout the complex, and there’s an underlying mystery (with weird, never-before-seen twists on traditional creatures) tying everything together. Discovering loot while unraveling the mystery is a delight for players—unlike so much of the campaign, this mystery is entirely solved by the time they leave the dungeon (without many lingering concerns). 

My players loved it, and I hope yours will too. Please feel free to give me some feedback; this is my first time putting together an adventure for sale, and while I did my best to make it as professional and polished as possible, I understand that there are always ways to improve!

Here’s the link to this adventure on the Dungeon Master’s Guild.