Out of the Abyss – Chapter 14 – The Labyrinth

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Very much like the Dark Lake, the Labyrinth is not a single place or “maze” but a gigantic region in the lowest reaches of the underdark. Because of its depth, It’s larger than the Wormwrithings. It is important to note that it’s not a two-dimensional plane, but rather a semi-spherical area, Which means that when the PC’s arrive, they enter the Labyrinth from its upper limits. When exploring it, they can move horizontally but also descend into the deepest parts of it. Many cities and forgotten realms have been buried and forgotten over Millennia  in this place. The PC’s could stumble upon unexplored dungeons or old cities during their travels through the Labyrinth.  The place is magically imbued in a way that disorients anyone who is inside (except minotaurs), similar to the Wormwrithings, there are countless caves and passages that seem to go everywhere and nowhere at the same time. Passages double up on themselves but seem to end in unknown places.

Any part of the Labyrinth that is in direct influence of Baphomet, becomes even more difficult to traverse. The laws of physics change, and symmetry and architecture defy the nature of the universe. Legends have been told about places where gravity is reversed and people, after getting lost, get back to their point of origin, only to find that they are now walking on the ceiling. Places were stairs go nowhere and doors move you back to your origin, or transport you somewhere else. Like the Escher Stairs.

Following on the “physics don’t make any sense here” trend. The party could at any point end up in an impossible place. Like a forest, jungle or tundra region of the Labyrinth.

Page 179 has a list of random encounters for PC’s traveling through the Labyrinth. As I always suggest, re-roll them before hand or just pick the ones that sound useful. I will soon write an article with extra encounters for the second part of the adventure. In the meanwhile, you can also draw inspiration from my Extra Encounters part 1 article.

The Adamantine Tower

This is the first set encounter in the labyrinth. There is a Daern’s Instant Fortress long forgotten in a cave. This is one of the most useful objects in D&D, apart from it being an adamantine nearly un-damageable tower. It can be used as a pocket “fireball” too. All that is good, the problem with this encounter is that it’s not correctly built. There are two gargoyles and two shadow demons protecting the tower. There is no challenge. Like other parts of the second part of the book, it seems like these encounters where actually for the first half, and were later moved to the labyrinth, and never edited. The PC’s probably have Dawnbringer and will wreck the shadow demons. The gargoyles won’t probably be able to do much either.

My suggestion is to have the shadow demons go guerrilla tactics. Hiding and attacking over and over to get their “sneak attack” damage. In the meanwhile, the 4 gargoyles attack and after 2 round, 1d6 Vrocks and 3d6 Manes Join the fight, they arrive from an adjoining cave. Now we have a more decent encounter for a level 11-12 party.

Spiral of the Horned King

After the Maze’s entrance room with the severed heads. The PC’s get to enter the Maze proper. They can encounter Gash, a mistreated gnoll who, depending on how he is treated, might help the PC’s navigate the Maze, or tell on them to his masters the minotaurs. This Maze is the perfect place to use some of the crazy locations ideas or weird physics.

The Maze is ridiculous in it’s challenge to a level 11-12 party too. It says it takes an hour to traverse at normal pace, with possible encounters every 30 minutes, and a Survival check DC 15 to get out. The encounter table in page 182 explains that a result from 1 to 14 has no monster encounter. What this means is that a party can get inside the Maze, get two non-combat encounters and then get a survival check to get out (DC15), with advantage if Gash is helping. And that’s it. Unless they do get the combat encounters, in which case they fight 2d4 gnolls or 1d6 minotaurs. Pretty boring in my opinion. We have to make some adjustments to this encounter to make it fun and challenging to a level 11-12 party.

For starters let’s forget about the encounter table and the encounters per hour. As I always recommend, it’s better if you come up and decide what’s exactly is going to happen and when. Decide what, if any, non combat encounters are going to occur inside the Maze. After that we have to build some creature encounters for the Maze. Actually any underdark denizen can appear in this area but the suggestion of gnolls and minotaurs is good. If you go for gnolls. 4d6 gnolls and 4 gnoll fang of Yeenoghu is a better challenge. They could also be mounting wargs in an additional encounter.  If you go for minotaurs, there is only one kind in the monster manual, but we also need beefier stronger kinds. I recommend to take the stats of the Barlgura demon and repurpose it as a minotaur, maybe just replace the bite attack with horns attack, and add a great axe. Bam ! you’ve got a demonic minotaur. Keep the resistances too.  For a tougher encounter, 4 minotaurs, 2d6 manes and a Glabrezu demon sounds awesome for a “boss fight” in the Maze.

When the characters have spent an hour fighting some awesome threats in the maze, they get to do a Survival check DC 20. If they succeed, they are out. If they don’t, they spent another hour there, and have one non-combat encounter and one combat encounter. After that the check is repeated. All this with advantage if Gash is helping. Now it’s more difficult to get out, as it should, but not impossible for a party. And still rewards the good treatment to Gash. Luck is crazy, so be ready with some back-up encounters, in case the PC’s spend more time that expected in the Maze.


This is a fun encounter, Filthriddens was a town of outcasts and refuges who for some decided to live here. They were raided often by minotaurs until recently, when one day Yeenoghu and his pack came and got rid of them. The cultist leader Grisha saw this, took a minotaur head and proclaimed a cult for Yeenoghu. Villagers who opposed him were killed and turned into ghouls. Grisha offers the PC’s to join his pack and enjoy the protection of Yeenoghu. If a fight breaks out, there are other 10 cultists and 6 ghouls ready to defend the town, this is probably too easy an encounter, consider adding 2 mages too.

This looks fun but there is nothing else to it, it’s an empty offering, by the book. If the PC’s refuse, Grisha is not violent and let’s them go. Avoiding the encounter altogether, that is good. If the fight happens, that’s good too. But if the PC’s accept. I recommend a small side quest.

Grisha guides them away from the town to a place were he meets up with two gnolls herding 4 hyenas.. Due to his devotion and the nature of the underdark, Grisha can communicate with the gnolls, who are not aggressive toward him or anyone with him. Then grisha, the two gnolls and the PC’s go on a hunt for minotaurs. Set a difficult fight, like the ones described previously in the Maze. After the fight, the hyenas feast on minotaur flesh and turn into full fledged gnolls (Madness check DC12). After that, the gnolls leave.

Grisha eats minotaur flesh too, and offers it to the PC’s as the “Blessing of Yeenoghu”, if they refuse, Grisha is disappointed and goes back to Filthriddens. If any PC accepts the gift, they get the Rampage ability from the gnoll stat block. they also get a new Bond: “I need to eat raw humanoid flesh”. The ability lasts for a week, after that it only works as long as the PC eats raw humanoid flesh that day. This condition can be removed with a Great Restoration spell.

March to Nowhere

A group of modrons came to the underdark 289 years ago as a part of their Great March, unfortunately for them, they haven’t been able to find their way back to Mechanus and have roamed the underdark and the Labyrinth ever since. It’s  really unlikely that a fight breaks out with the modrons. Most likely, the modrons will join the PC’s after a successful Charisma check. The modrons know the exact position and distance to the Maze Engine, which they call the Orderer. This alone is enough incentive to bring them along with the party.

They can disclose to the PC’s some of the nature of the Maze Engine and explain that it is meant to change reality in order to bring order to chaos. In other words, its original function was to transform reality so that it resembles Mechanus. But this one is broken and the results of using it are hard to predict.

Yeenoghu’s Hunt

This is serious business, an encounter with one of the demon lords.  The PC’s come across Yeenoghu and his pack of gnolls and hyenas. Yeenoghu is fighting a Goristro (which is important because the PC’s need its heart). Yeenoghu beats the shit out of the Goristro and feeds the hyena pack with the demon’s flesh. They evolve into gnolls and this transformation provoques a madness check.

By the book (page 184), It advices that the PC’s should hide and wait until Yeenoghu leaves (or die). Then the PC’s can go and fight a smaller pack of 8 gnolls and one gnoll pack lord. After that, they can harvest the Goristro’s heart and Yeenoghu’s blood from the Goristro’s horns. And this is boring ! the suggested fight is a cakewalk for a level 11-12 party.

There are two alternatives here, one is to bump the gnoll encounter, maybe by adding some extra demons, a second wave of gnolls with demon reinforcements, or gnolls mages. I find it very anti-climatic to have a crazy easy fight because it was badly planned. The other alternative is the very serious one. Fighting Yeenoghu.

Yeenoghu is crazy strong and very scary, however, a level 11-12 optimized party could consider facing the demon lord right there.  It is a very difficult fight but a party of 4 and 5 can take on the demon lord and its pack. Only a well optimized party with well rehearsed combat tactics can dare this challenge, but it is possible, I saw it happen twice in my games.  By the way, it has to be taken into account that Yeenoghu will not have it’s full HP because of the fight with the Goristro, a 20% drop is enough. If your party is strong and they are considering fighting Yeenoghu, don’t discourage them, it will be awesome when they defeat him. Maybe a PC or two will die but the victory will be sweet. It will also give them access to Yeenoghu’s cursed flail. Which I intend to stat in a different article. But if you’re interested, we played with a house rule that said that Demon Princes (Orcus, Demogorgon and Graz’zt) couldn’t be damaged with any weapon, except demonic weapons. In OoTA there are three, Yeenoghu’s Flail, Baphomet’s Great Axe and the Wand of Orcus. The Wand of Orcus changes size and attunes instantly to whoever picks it up in the final confrontation, so the other demonic weapons could do that too, and it adds to the reason why defeating Yeenoghu or Baphomet in the Labyrinth is important.

The Gallery of Angels

This is a sad place, eight angels were confined to this corner of the underdark for crimes they committed eons ago. The angels are turned to stone, yet they are still conscious and aware of their surroundings, unable to do or act in any way. Touching any statue (to chip apart a feather) causes the PC to trigger an effect that depends on the angel. The DM has to describe each angel’s position and facial expression. This a very creepy place. Although it seems like an easy thing to do, due to the angel’s effect, the PC’s might end up fighting each other or receiving damage or orders from the angels. They can never be released from their fates, even if the statues are destroyed, their souls remain embedded in the stones. Forever trapped.

A group of PC’s might try different kinds of magic to try to release them but everything will fail. If a cleric tries to use a divination spell such as Commune, you can have the character’s god tell him directly that the angels where placed here eons ago, for crimes committed against their faiths. Different gods have placed angels here for confinement and one of the angels, actually belongs to the character’s faith, and was placed here by his/her god. The god can also explain that this is god magic and that it’s useless to try to break the spell.

The Maze Engine 

Much has been said and fathomed about the Maze Engine. The device was built by modrons back in Mechanus, it’s meant to bring order to chaos but this one is broken. If activated, its effects cannot be predicted and will malfunction once and again until it falls into the lava.

Baphomet left a loyal servant to guard the Engine, a Nalfeshnee called Slaughtertusk. He is supposed to play as long as possible with intruders. My personal suggestion is to change this a bit, when the PC’s arribe, Slaughtertusk send a message to Baphomet saying that they have visitors. Better yet, if Yeenoghu was defeated previously, then the message is even more urgent and Baphomet will get there as soon as possible, unfortunately he is far away. Slaughtertusk is very intelligent (INT 19) and will try to play with the PC’s minds or offer them things to make them discuss and wait and consider, while Baphomet arrives. He can offer them to join Baphomet’s ranks, as they are very impressed with the PC’s accomplishments. Or he can try to make them think about their actions in the underdark. Whatever he says he most be portrayed as supremely intelligent and cunning, despite his bestial appearance. Unlike the book (page 187) Slaughtertusk summon Vrocks as soon as the fight starts. And will teleport up in the air and attack them from the air and only fly down to attack spell casters or other squishy PC’s.

After he is defeated, the PC’s will have access to the engine, any modron with the party can assist in making the Engine function. He can explain that they have to be physically inside the engine for it to work, PC’s might be deceived into believing that this is a “wish machine”. Once the engine starts, the way it works is just like explained in page 187. Rolling for random results every round and hoping for the best. It gets to roll for 10 rounds before falling into the lava. Anything can happen here, PC’s could fall to the lava or be petrified, an NPC could come back to life. The table of different results on page 188 is very varied. The most important thing that can happen is the one you get if you roll 81-100. This causes the engine to banish any extraplanar creatures back to their planes. Effectively destroying Yeenoghu and Baphomet and all their demon followers back to the Abyss.

I recommend to read all the different options in advance to be ready for all the different effects. Additionally, you might want to come up with your own effects to be used in the Maze Engine, remember that anything can happen, an old acquaintance might show up, a magic item can be generated or destroyed, a teleport spell might send a PC somewhere far. Make it unique.

One more thing, there are two options in the Maze Engine table that can destroy your game. One transports the PC’s back to the past, to Velkynvelve. There is no mention of a turn back, so there are two alternatives here. You could “restart” the campaign and play again most of it (boring). Or you could give them something like 10  minutes in the past to try the prison escape again and maybe telling sensitive information to the rest of the NPC’s. possible changing the past. After the time, they are teleported back to the future in the Maze Engine.

The other option is the one you get when rolling 01, this destroys all the magic objects. This will disrupt the campaign and make the players super angry. But there is an alternative I wrote about a long ago. Instead of having them destroyed, have them absorbed in a vortex and transported to Mechanus. Now you have a side-quest. Got to Mechanus with the modrons and recover the magic items.  If you want to check out this amazing planar quest read this article.

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5 thoughts on “Out of the Abyss – Chapter 14 – The Labyrinth

  • Hi Derek,

    In this article you mention that you let your players have Yeenoghu’s flail and Baphomet’s glaive after they defeated them, and said you intend to stat them in a different article. However, I wasn’t able to find that article. Would you either point me in the right direction or post the stats here?

    I followed your suggestion of having Heartcleaver drop after my players defeated Baphomet in the Labyrinth. They were supposed to just survive until the Maze Engine activated, and most of my players aren’t power gamers or great tacticians, and the paladin with Dawnbringer sat out the whole fight, thanks to Baphomet’s Maze spell, so I didn’t stat the weapon up ahead of time, thinking that they wouldn’t kill him. However, they did end up killing Baphomet, with several rounds to spare before the Maze Engine activated.

    I promised them the weapon would have stats when they identify it at the beginning of next session and I was just going to base it off the weapon Baphomet uses in his stat block. However, I’ve since realized that Heartcleaver is TERRIBLE. After looking more closely at his stats, I realized the glaive is +0 and it actually does less damage than a non-magical huge glaive should do. It only does 4d6+10 damage in his hands. A completely non-magical huge glaive would do 3d10+10 damage.

    So, I’ve already told my players they have the weapon and that it changes sizes to fit the wielder, as you suggested. I’m curious how you handled this and made it into a decent weapon. Did you not have its damage dice change when it resizes?


    • Hello Bryan. I never stat those weapons in any part of my guide. It’s something that slipped my mind and never happened, but this is what I did when I ran the campaign. I never gave stats for the Glaive since my characters didn’t ever use it. But they used the flail, and this is what I did. It was a Nine-lives Stealer weapon with a +3 magical bonus. Damage was 3d10 + the PC modifiers. After each battle using it you had to roll a charisma or wisdom save, don’t remember exactly or become chaotic evil permanently. This deterred my players from using the weapon too often since the price was to high for them. The difficulty was 13.

  • Thank you for the feedback. I think I’ll make the glaive do 3d10 + STR damage and give it the Berserker Axe’s downside, to discourage overuse.

    My players wouldn’t care at all about becoming chaotic evil. In fact, early on in the campaign I had to inform most of them that, regardless of what their character sheet said, they were evil, based on their decisions during the campaign. Several of them were surprised when I told them and apparently didn’t realize that if you continually do evil things, you’re evil. But most of them embraced their new alignments and never looked back.

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