Charles Rampant
Adventurer
Hey all,
For a Waterdeep campaign that I’m starting next week, I was thinking about what I wanted to do with Undermountain. I’m going to adopt something akin to skill challenges from 4e and the Journey rules from AiME, in order to create a mechanical system for exploring the complex, rather than relying on traditional maps. The below is an attempt to render a system, and I’m hoping for feedback and thoughts on it.
The Reason
For those who are not familiar, Waterdeep is a large metropolis (100,000 population in winter, 600,000+ population during the summer) with a heavily mercantile theme, and it just so happens to be sitting on the same site as ancient Elven and Dwarven cities once did. The entire plateau that it sits on is honeycombed with mines, tunnels, caves, and entire dungeon complexes. The greatest part of this honeycomb is the creation of a mad and immortal wizard named Halaster Blackcloak, who quite likes watching adventurers die, and so he stocks it with treasure to lure them in, and traps and monsters to put them down. Back in 2e there were some large supplements for it, which rather erratically mapped out several levels of the complex; even though they were not complete, as in the accompanying text didn’t explain every room, and the maps only covered half of the levels described, they still represent a mammoth dungeon.
However, I don’t want to use this. There are a couple of reasons. Firstly, it makes the complex rather mundane, if it all exists on bits of paper; the players can soon start learning the routes, or mapping it out themselves, and though I can move tunnels around and close doorways, it seems like soon the ‘mystery’ of the complex would be lost for large portions. In addition, I really can’t be bothered flipping between 50 pieces of A4 paper with the map on it, trying to work out where the characters are. By avoiding maps, I can have dramatic moments (“You find another party!”, “Dead bodies in the corridor to the side”, “Orc voices behind”) without needing to do a lot of work to set those things up in advance - they can simply be results on the table. Lastly, and perhaps more importantly, by using these mechanics I hope to really establish and reinforce a tone of wandering around in the darkness; if anyone remembers the section of Magician where Tomas finds Ashen-Shugar’s armour, then that is my inspiration, as well as Moria.
Once the bulk of the dungeon is treated in this way, I can then insert entire ‘normal’ dungeons into it - the Besilmer sections of PotA, White Plume Mountain, the Dripping Caves from SKT, the Amber Temple from CoS, that sort of thing. The players would hear about these things (from people in the Yawning Portal, presumably for a price), assemble their in-character scraps of maps, list of portal routes, and rations, and set off in the effort to find the specific dungeon location that they are looking for. In other words, I simply use Undermountain as a dumping ground for all of the dungeons that I fancy using, without needing to explain how they fit together, where precisely the entrance to them is, or needing to maintain continuity between locations on a map.
One last note; we can quietly ignore Teleportation abilities for this purpose, with perhaps a handwave of ‘only the portals and teleportation circles that Halaster himself has established are safe’, meaning that I can insert a quite route into a specific place if it suits my purposes, but the party can’t just ignore this system when they reach level 9.
The Party
The party will assign a set role to every member of the party. No role can be duplicated, with the exception of Lookout, nor can any one character fulfil more than one role. The roles all have different jobs to do, and will hopefully help reinforce character abilities and niche protection.
The Guide - the person who will navigate the party from the Yawning Portal (or another entrance point, such as Skullport or the sewers) to their destination. Required Skill: Survival.
The Arcanist - the person who will examine runes and other magical markings, will determine which portals are safe to use, and deactivate any barriers that they find. Required Skill: Arcana.
The Lockpicker - the person who finds, examines, and deactivates traps, as well as opening locked doors. Required Skill: Thieves’ Tools.
The Lookout - the person or persons who will keep watch, ensuring that if the party is being followed or is about to be attacked, that they know about it. Required Skill: Perception.
Note: in AiME, there was a role for a hunter, who gathered supplies, but I’m not convinced that this is a logical task in a dungeon located directly under a city. We’re talking about journeys of 1-3 days at most, not weeks or months. However, I do feel that another position would be good, if only because I’ll have six players; I considered The Face, but that also felt rather weak in concept, and would require them to meet other groups really often to give that player satisfaction. Perhaps The Scientist would make sense - the person who rolls History or Religion to determine what area they are in, but again that feels like a diminution of the Guide, not to mention it would probably be the same person who had good Arcana, which isn’t perfect. Other suggestions would be gratefully received.
The Tables
For this system, we roll on three tables during a journey; the departure, the events, and the arrival. Again, we’re leaning heavily on AiME here, but I’m not planning on using their table structure. Instead, these will be fairly simple tables which operate around the assumption that the players have roughly a +7 to their roll (proficiency+stat mod for a level 5+ adventurer), and that the characters generally succeed on their tasks. I’m also inclined to say that Inspiration, Lucky, and other such abilities cannot be used on these rolls, to keep the odds reasonably simple to calculate.
The below categories were calculated on the assumption that characters with +7 or so are not going to get numbers below eight very often, which is why natural 1 is the number that I start with. I have ‘critical fails’ on skill checks as a house rule, it’s worth noting.
The Departure table is the responsibility of the Guide, and it helps give modifiers to the rest of the group. ‘Failure’ is not an envisaged option; in other words, the Guide’s roll doesn’t determine if the players arrive at their destination, it determines how they arrive. A bad roll means they get beat up, a good roll means they have an easy trek. Mechanically, this will give modifiers to the rest of the rolls in the journey; if the Guide fluffs it, then the party is led into enough danger and troubles that the other characters find their tasks more difficult.
Nat 1: catastrophic trip, with the party led astray into enemy territory. All other roles (including multiple lookouts, if relevant) must roll against DC 15, and each failure gives the party members a level of exhaustion that cannot be removed while inside Undermountain. The party must then roll on the following tables as normal.
2-9: bad journey, with the party either having disadvantage on events or on arrivals.
10-15: normal journey, no modifiers.
16-20: good journey, with either the Events or Arrival stages getting advantage (party choice).
21+: great journey, the party has advantage on both subsequent stages.
The Events table is basically ‘stuff that happens’, and it is where the Arcanist and Lockpicker come into play. Both roll, perhaps with advantage or disadvantage as determined by Departure.
Nat 1: A disaster of some sort. The entire party gains a level of exhaustion.
2-9: The character sets off a trap, wrongfully identifies a portal and leads the party into enemy territory, or something similar. Every character in the party loses a quarter of their total hit dice, and do not regain them until they leave Undermountain.
10-15: Normal outcome, with the party overcoming the challenges.
16-20: A good outcome, with the character managing to either find some treasure on the journey (1d100gp) or information about another dungeon in Undermountain (DM’s discretion).
21+: The character expertly avoids the trouble, and both gains 2d100gp for the party, and grants advantage on one of the Arrival rolls.
The Arrival stage is for the lookouts, and represents them helping the party to avoid ambushes and unnecessary combats on the way to their destination. Each lookout has to roll, on the assumption that they are watching different directions, or taking watch at different times.
Nat 1: The party is led into an ambush. Each party member must make a death saving throw, and keep the results for the rest of the dungeon.
2-9: The party gets into an unnecessary combat. Each character gains a level of exhaustion.
10-15: Normal, with no enemies spotted.
16-20: The lookout finds a stash of healing potions, curative mushrooms, or a magical rejuvenation chamber. Each party member can undo one of the negative effects incurred from rolling on these tables, their choice.
21+: The lookout spots something very helpful for the party’s expedition. They may either find 2d100gp, or gain some useful information about the dungeon that the party is travelling to (DM’s discretion).
Closing Thoughts
I hope that the above makes sense, and is not total gibberish to you! The intention is that the party will usually arrive safe and sound, but will sometimes have found some minor treasure on the way, and sometimes have gotten into some tough trouble that leaves them somewhat banged up for their dungeon escapades. It also hopefully lets everyone feel involved. However, I don’t think that this is as developed as it could be. For example, I’d like more decisions; it’d be good if the Lookouts occasionally got to decide between a tough fight now, or hiding in a potentially dangerous location. I’d also really like a way of having other skills come up from time to time - Athletics especially, since Fighters and Barbarians don’t always get sufficient mention in these areas. My main concern though is that I don’t want this to turn into a big thing; I just want a way of communicating how the characters get from the Yawning Portal to the dungeon entrance, and the difficulties they faced in doing so.
Thanks for reading this far. Any thoughts and feedback that could be offered would be greatly helpful!
For a Waterdeep campaign that I’m starting next week, I was thinking about what I wanted to do with Undermountain. I’m going to adopt something akin to skill challenges from 4e and the Journey rules from AiME, in order to create a mechanical system for exploring the complex, rather than relying on traditional maps. The below is an attempt to render a system, and I’m hoping for feedback and thoughts on it.
The Reason
For those who are not familiar, Waterdeep is a large metropolis (100,000 population in winter, 600,000+ population during the summer) with a heavily mercantile theme, and it just so happens to be sitting on the same site as ancient Elven and Dwarven cities once did. The entire plateau that it sits on is honeycombed with mines, tunnels, caves, and entire dungeon complexes. The greatest part of this honeycomb is the creation of a mad and immortal wizard named Halaster Blackcloak, who quite likes watching adventurers die, and so he stocks it with treasure to lure them in, and traps and monsters to put them down. Back in 2e there were some large supplements for it, which rather erratically mapped out several levels of the complex; even though they were not complete, as in the accompanying text didn’t explain every room, and the maps only covered half of the levels described, they still represent a mammoth dungeon.
However, I don’t want to use this. There are a couple of reasons. Firstly, it makes the complex rather mundane, if it all exists on bits of paper; the players can soon start learning the routes, or mapping it out themselves, and though I can move tunnels around and close doorways, it seems like soon the ‘mystery’ of the complex would be lost for large portions. In addition, I really can’t be bothered flipping between 50 pieces of A4 paper with the map on it, trying to work out where the characters are. By avoiding maps, I can have dramatic moments (“You find another party!”, “Dead bodies in the corridor to the side”, “Orc voices behind”) without needing to do a lot of work to set those things up in advance - they can simply be results on the table. Lastly, and perhaps more importantly, by using these mechanics I hope to really establish and reinforce a tone of wandering around in the darkness; if anyone remembers the section of Magician where Tomas finds Ashen-Shugar’s armour, then that is my inspiration, as well as Moria.
Once the bulk of the dungeon is treated in this way, I can then insert entire ‘normal’ dungeons into it - the Besilmer sections of PotA, White Plume Mountain, the Dripping Caves from SKT, the Amber Temple from CoS, that sort of thing. The players would hear about these things (from people in the Yawning Portal, presumably for a price), assemble their in-character scraps of maps, list of portal routes, and rations, and set off in the effort to find the specific dungeon location that they are looking for. In other words, I simply use Undermountain as a dumping ground for all of the dungeons that I fancy using, without needing to explain how they fit together, where precisely the entrance to them is, or needing to maintain continuity between locations on a map.
One last note; we can quietly ignore Teleportation abilities for this purpose, with perhaps a handwave of ‘only the portals and teleportation circles that Halaster himself has established are safe’, meaning that I can insert a quite route into a specific place if it suits my purposes, but the party can’t just ignore this system when they reach level 9.
The Party
The party will assign a set role to every member of the party. No role can be duplicated, with the exception of Lookout, nor can any one character fulfil more than one role. The roles all have different jobs to do, and will hopefully help reinforce character abilities and niche protection.
The Guide - the person who will navigate the party from the Yawning Portal (or another entrance point, such as Skullport or the sewers) to their destination. Required Skill: Survival.
The Arcanist - the person who will examine runes and other magical markings, will determine which portals are safe to use, and deactivate any barriers that they find. Required Skill: Arcana.
The Lockpicker - the person who finds, examines, and deactivates traps, as well as opening locked doors. Required Skill: Thieves’ Tools.
The Lookout - the person or persons who will keep watch, ensuring that if the party is being followed or is about to be attacked, that they know about it. Required Skill: Perception.
Note: in AiME, there was a role for a hunter, who gathered supplies, but I’m not convinced that this is a logical task in a dungeon located directly under a city. We’re talking about journeys of 1-3 days at most, not weeks or months. However, I do feel that another position would be good, if only because I’ll have six players; I considered The Face, but that also felt rather weak in concept, and would require them to meet other groups really often to give that player satisfaction. Perhaps The Scientist would make sense - the person who rolls History or Religion to determine what area they are in, but again that feels like a diminution of the Guide, not to mention it would probably be the same person who had good Arcana, which isn’t perfect. Other suggestions would be gratefully received.
The Tables
For this system, we roll on three tables during a journey; the departure, the events, and the arrival. Again, we’re leaning heavily on AiME here, but I’m not planning on using their table structure. Instead, these will be fairly simple tables which operate around the assumption that the players have roughly a +7 to their roll (proficiency+stat mod for a level 5+ adventurer), and that the characters generally succeed on their tasks. I’m also inclined to say that Inspiration, Lucky, and other such abilities cannot be used on these rolls, to keep the odds reasonably simple to calculate.
The below categories were calculated on the assumption that characters with +7 or so are not going to get numbers below eight very often, which is why natural 1 is the number that I start with. I have ‘critical fails’ on skill checks as a house rule, it’s worth noting.
The Departure table is the responsibility of the Guide, and it helps give modifiers to the rest of the group. ‘Failure’ is not an envisaged option; in other words, the Guide’s roll doesn’t determine if the players arrive at their destination, it determines how they arrive. A bad roll means they get beat up, a good roll means they have an easy trek. Mechanically, this will give modifiers to the rest of the rolls in the journey; if the Guide fluffs it, then the party is led into enough danger and troubles that the other characters find their tasks more difficult.
Nat 1: catastrophic trip, with the party led astray into enemy territory. All other roles (including multiple lookouts, if relevant) must roll against DC 15, and each failure gives the party members a level of exhaustion that cannot be removed while inside Undermountain. The party must then roll on the following tables as normal.
2-9: bad journey, with the party either having disadvantage on events or on arrivals.
10-15: normal journey, no modifiers.
16-20: good journey, with either the Events or Arrival stages getting advantage (party choice).
21+: great journey, the party has advantage on both subsequent stages.
The Events table is basically ‘stuff that happens’, and it is where the Arcanist and Lockpicker come into play. Both roll, perhaps with advantage or disadvantage as determined by Departure.
Nat 1: A disaster of some sort. The entire party gains a level of exhaustion.
2-9: The character sets off a trap, wrongfully identifies a portal and leads the party into enemy territory, or something similar. Every character in the party loses a quarter of their total hit dice, and do not regain them until they leave Undermountain.
10-15: Normal outcome, with the party overcoming the challenges.
16-20: A good outcome, with the character managing to either find some treasure on the journey (1d100gp) or information about another dungeon in Undermountain (DM’s discretion).
21+: The character expertly avoids the trouble, and both gains 2d100gp for the party, and grants advantage on one of the Arrival rolls.
The Arrival stage is for the lookouts, and represents them helping the party to avoid ambushes and unnecessary combats on the way to their destination. Each lookout has to roll, on the assumption that they are watching different directions, or taking watch at different times.
Nat 1: The party is led into an ambush. Each party member must make a death saving throw, and keep the results for the rest of the dungeon.
2-9: The party gets into an unnecessary combat. Each character gains a level of exhaustion.
10-15: Normal, with no enemies spotted.
16-20: The lookout finds a stash of healing potions, curative mushrooms, or a magical rejuvenation chamber. Each party member can undo one of the negative effects incurred from rolling on these tables, their choice.
21+: The lookout spots something very helpful for the party’s expedition. They may either find 2d100gp, or gain some useful information about the dungeon that the party is travelling to (DM’s discretion).
Closing Thoughts
I hope that the above makes sense, and is not total gibberish to you! The intention is that the party will usually arrive safe and sound, but will sometimes have found some minor treasure on the way, and sometimes have gotten into some tough trouble that leaves them somewhat banged up for their dungeon escapades. It also hopefully lets everyone feel involved. However, I don’t think that this is as developed as it could be. For example, I’d like more decisions; it’d be good if the Lookouts occasionally got to decide between a tough fight now, or hiding in a potentially dangerous location. I’d also really like a way of having other skills come up from time to time - Athletics especially, since Fighters and Barbarians don’t always get sufficient mention in these areas. My main concern though is that I don’t want this to turn into a big thing; I just want a way of communicating how the characters get from the Yawning Portal to the dungeon entrance, and the difficulties they faced in doing so.
Thanks for reading this far. Any thoughts and feedback that could be offered would be greatly helpful!

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