Based in Southern Oregon, Fiddleback is a blog and portfolio by Brian Casey. His posts explore tabletop gaming and other topics through examination of RPGs, boardgames, and more. He is a freelance tabletop game editor and writer, and podcaster.

Fiddleback vs. Dead in Thay

Fiddleback vs. Dead in Thay

Dead in Thay, a one hundred six room mega-dungeon of evil wizards, dangerous beasts, and things that simply should not exist. Deep inside the Doomvault lay the phylacteries of Szass Tam and his corrupted servants. Will the PCs foil the plans of Tam and destroy his phylactery, or will they lose their lives and wander forever as undead?

The fifth adventure in Tales From the Yawning Portal, Dead in Thay represents yet another weird curiosity of Dungeons and Dragons. In 2014, on the cusp of a new edition of the game, Wizards of the Coast needed a way to playtest not just their new ruleset, but the many creatures and NPCs as well. Dead in Thay was the solution and was released to Organized Play coordinators and GMs for testing with what was then called the D&D Next rules.

In order to test as many things as possible in a relatively short time, the decision was made to design a dungeon that several parties could enter at once, have little chance of encountering each other, but still work towards a common goal. That meant designing a variety of environments and populating them with a variety of monsters and NPCs, including enough rooms to keep people busy over the course of the playtest. In addition, they had to work out a way to prevent people from working the same sectors of the dungeon simultaneously.

So, the Doomvault was devised. While it is 105 rooms of adventure, it is also divided into 9 distinct sectors. Each of these sectors is locked off from the others by means of special gates requiring special keys. Keys to be found through the course of the adventure. A party could choose what sector they wanted to enter and no other party was allowed to choose that sector for their session. The need to collect keys that opened two different kinds of special gates meant that PCs couldn’t advance into another party’s area unless the right keys were in hand. Finding the keys usually meant a thorough search of their own sector, a requirement that virtually guaranteed everyone involved would be finishing in about the same time at the Organized Play events, effectively keeping the parties out of each other’s way.

Within each sector, comprised of ten to fifteen areas each, a different creature theme prevails. From the constructs in the Golem Laboratories, to aquatic threats in the Predator Pools, to the wild beasts of the Forest of Slaughter, each sector has its own theme, selection of monsters, and appropriate encounter areas for each. Mixed among the other denizens of these sectors is a selection of the Red Wizards of Thay, both the faceless NPC type and named characters of some significance. Toss in a variety of wandering encounters appropriate for each sector and call it good.

It seems to have worked. Players played, tests were made, and adventure was had. The setup, execution, and gameplay with multiple groups going in at once, reporting their results to each other, and working towards the same end goal, was sufficiently popular to warrant a release of the playtest module to the general public through the Dungeon Master’s Guild. Anyone who wants to can play the original adventure as written and has been able to do so since June of 2014. By most accounts, the entire event, and so the adventure, was very popular.

The version of Dead in Thay presented in Tales From the Yawning Portal differs in a few key ways from the playtest version. NPC stats are less of a guess as to what might work and have been standardized to the final rules of 5e thanks to that same playtesting. A sort of pre-adventure adventure dealing with the assault on some Elemental Nodes to both tie-in Dead in Thay to a pre-existing storyline and to lead up to the adventure here has been eliminated. A quantity of instructions involved in running it as part of Organized Play has been removed. And the entire Doomvault has been tuned to run for 9th level characters rather than the somewhat broader, and lower, range of 6th to 8th for the playtest.

Of the nine sectors of Dead in Thay, only seven are initially available to the party thanks to starting points present in those sectors. The keys needed to access further sectors, called Glyph Keys, can be matched up with each other or various other elements of the dungeon to provide entrance. Four keys are special, they are distributed around the map and provide access to a sector unconnected to the other 8, the Temples of Extraction. From the Temples, the PCs will make their final assault on the Phylactery Vault and the challenges there.

Along the way, they will acquire pieces of lore which will give them the clues needed to figure out what they have to do to enter both the Temples and the Vault as well as various clues to the rest of the Doomvault. In addition, should any of the characters die, they have the option to come back as soul-bound characters, alive again, but incapable of surviving outside the Doomvault and in danger of becoming fully undead the longer they remain in this state. The only hope is to enter a particular room in the dungeon and reverse the process.

Meanwhile, as the DM, it will be your job to administer all this. You’ll be keeping track of rumors given (there is a list), the order they’ve been given in, which gates the Glyph Keys the party possesses go to and which ones are still needed, which of the essential black gates have been inactivated, the state of the dungeon and its inhabitants as the PCs progress, the shifting locations some of the NPCs are in, the alert level of the dungeon (which affects the frequency and difficulty of the various random encounters), what sections have been explored, and, of course, the regular play of the game.

Now, this seems like a lot to do, and it is. Originally, the adventure had a couple of coordinating tiers to help you do this, the event organizer and a team captain, to share information between groups and assist in keeping track of things. That, of course, no longer exists for the DM attempting to play the adventure at home. You’re on your own.

Also on their own is your group of players. Unless you’ve set up a special event of some sort, Dead in Thay, becomes a vast, unexplored series of rooms with odd requirements for going from place to place and only one group of adventurers to deal with it all. If this is what your group wants to do, then more power to them.

Unfortunately, while Dead in Thay has a variety of critters and locations to fight in, what it truly lacks is a variety of encounter types. Clearing two sectors will reveal that much of the remaining dungeon will follow a similar pattern: Enter a sector, hunt the keys you need to open up the gates (of which each sector has many), kill or otherwise eliminate the things preventing you from getting the keys, get some lore, then (if you know enough lore) disable a black gate (of which each sector has four), and leave. This repeats for all but one sector.

So, 106 rooms of pretty much that sequence of events awaits you. Except it doesn’t. Well, not exactly.

See, since you have only a single party tackling the Doomvault, they only need to disrupt 6 black gates to open access to the 9th sector and trigger the endgame. Just six. And you remember up there where I said each sector has 4 black gates? That means, at most, your party only has to go to one and a half sectors to get enough gates to disrupt and begin the ending and head to the Temples of Extraction and Phylactery Vault. Provided they know the lore needed to tell them this and they are thorough searchers.

That’s the rub, that lore. They have no instructions about how to get into the Temples of Extraction and can only learn it through collecting lore from NPCs they encounter. Of the nineteen pieces of lore available to learn, only four, given in a restricted sequence, tell the PCs how to get into the Temples. Not all NPCs can provide lore, and of those that can, they only provide one or two pieces off a specific list of lore. Many of those only provide lore under specific conditions like bargaining for their life. PCs will be forced to chase all over the complex to collect as much lore as they can to get the information they need, there’s not enough lore available in any one sector to do otherwise.

The other limiting factor is the need to find one of four special glyph keys scatted throughout the complex to access the black gates in the Extraction sector. There is little in the way of clues given to help the PCs find them; they’re forced to wander sector to sector looking.

Fortunately, PCs can go back to the gatehouse where they started and meet up with other groups of PCs to… copy… Glyph Keys... and share… lore…. Oh, wait. You can’t, can you? Because you’re playing this with just one party. Well. Better get them moving. They’ve got a lot of ground to cover.

The suggestion is made that characters could level up to as much as 11th level or more if they run the entire dungeon, which is nice. They are going to need it for the final encounter. Anything less than that and the encounter becomes more than deadly instead of just deadly. If they lose, they can, of course, elect to become soulbound and keep going to sectors looking for encounters they missed or hoping sufficient random encounters occur to boost them up. Except, since the final encounter is a demilich, it seems reasonably certain that the PCs are going to be in really bad shape for fighting anything (especially if you remember to use the demilich’s lair actions and traits).

The final encounter itself is unique and interesting. It takes place on the inside of a hollow pyramid and every wall is a floor thanks to some funky gravity. Inside, the PCs will be asked to disable three of twelve sepulchers, thereby eliminating the phylacteries stored within each, in order to end the game and emerge victorious.  Assuming they survive the demilich.

From there it is a hop, skip, and a jump to the conclusion and, if anyone has been soul bound and not corrected it, some bad news. Or good, depending on the PCs point of view.


Dead in Thay, upon examination, is clearly a dungeon that is designed and intended for multiple groups to work on at once. No particular care has been taken to make it more viable for solo groups aside from level adjustments.  It will quickly become a tedious, multi-session slog from room to room looking for that one key or that one rumor the party needs to just get the hell out if they go it alone. Sure, they’ll see some different environments and fight different creatures, but they won’t actually be doing anything different from start to finish. Even room gimmicks repeat themselves in a given section. If there is a special circumstance in room x, then that circumstance repeats, with only minor variation, in rooms y and z.

There is an overall sense that the designers of Dead in Thay took the middling levels of NPCs and monsters, sorted them into groups by type and then plopped them down wherever convenient. This is perfectly fine if you are designing a playtest to get as much tested as quickly as possible. String a bit of story about a wizards training ground around it and get it out to the testers. No problem.

However, this approach does not suffice for the majority of gamers. If a group intends to do the entire Doomvault as written, they are looking at roughly 26 sessions (assuming approximately 4 combat encounters per session, a not unreasonable number) to complete the entire adventure. It’s possible to do it in fewer if they happen to hit the right rumors and find the right keys, but even that is going to take a sizeable chunk of time to complete. There has to be more to an adventure than just going room to room repeating the same few activities every time. There’s not enough meat on the bones here to really make it worth half a year of playing. The players could, and should, be doing much, much more interesting things with that time.

The fact that the adventure set up forces solo PC groups to go over the whole map to accomplish goals that could be accomplished very early on speaks to the level of single group modification that did not take place. There is, however, a way to fix this.

Rather than having the adventure encompass the full map, make a few modifications of your own. Pick two of the sectors you think your PCs would appreciate, or have them select two of their own they like the look of. Pull those together however you like, separate them with the Master’s Domain section and arrange them so they more or less fit, then tack on the Temples of Extraction. That gives them somewhere around 50 rooms to explore. Redistribute the rumors and required Glyph Keys (including the crucial Extraction keys) into these areas if they aren’t present already. Then run that instead of the whole thing. Bring PCs in at 10th level so they have a shot at leveling up once and being prepared for the Phylactery Vault encounter. They still get a long adventure with plenty of encounters, but one that lasts just about long enough to maintain interest without over staying its welcome and eating up valuable time for better adventures. As a bonus, you can run this set up again later with two different rooms of choice.

Dead in Thay lives up to the ‘deadliest dungeons’ pick, if only because it is intended to kill players so they can experience its soul bound mechanic. The final encounter is likely to be a killer as well. A question remains, though: Would it have earned its reputation as deadly if all the encounters and NPC stats had been solidified for the new edition and if multiple groups hadn’t been in it at once?

That’s a hard call to make. On the one hand, it may be that the number of PCs in the adventure simply meant that more deaths occurred on a session to session basis because there was more to die. On the other, issues with encounter balance and NPC stats may have meant more deaths occurred more or less because of a mistake that was corrected later in the final design. Either one of these factors, or both, may have influenced its perception as one of the deadliest dungeons.

As it stands, the length of Dead in Thay, as well as it’s apparent intent to make sure players experience the soul bound mechanic and the challenge level of the final encounter, will probably mean a more than average number of PC deaths on a per adventure basis overall. As usual, more careful players will probably have a better experience than those who are hasty.

There is no particular compelling reason to play Dead in Thay except for its length. Better lengthy experiences can be had running any of the other adventure storylines released for 5th Edition. If, for some reason, a DM and Party want to see the adventure used to play test D&D Next, then this is the choice. But it is also a choice that has been available for a few years now; aside from the level tuning in Tales From the Yawning Portal, there’s no real difference between the two. Much of its popularity seems to come from its playtesting experience. If you must sample it, sample it with the adjustments given above. There’s just not enough here to recommend running the entire thing and there are certainly at least three adventures that could have taken up the page count and offered better experiences.

Up next, Against the Giants.

Fiddleback vs. Against the Giants

Fiddleback vs. Against the Giants

Fiddleback vs. White Plume Mountain

Fiddleback vs. White Plume Mountain