It’s not like your average dungeon or lich cave has OSHA approved vents, fans or electric lighting. Your average party, without specific magical aid, is burning torches and lanterns in unventilated spaces.
ETA: if you’re going to run carbon monoxide, etc rules, your supply shops should stock and recommend caged canaries to anyone buying large quantities of torches and lamp oil, dungeoneering/mining gear, etc. People would know about it and have figured out a primitive solution that merchants would be happy to capitalize on if this is an in-world issue.
People don’t realize how dangerous the air in confined underground spaces can be
Most underground lairs would have a draft so the air is viable. Because most things living underground, even in the underdark, need to breathe. Which is why liches and other intelligent undead would be so dangerous. They don’t so they can build without concern for that.
Unrelated, but interesting username you’ve got there. Sounds like some fun flavour to add to a campaign world.
The Interplanar Union of Kobolds (IUK, pronounced “yuk”) is my favorite long-running gag I work into every campaign. Their HQ is in Sigil, but they have locals on most major planes. No longer will the long-suffering kobold serve its draconic masters! A fair day’s boobytrapping for a fair day’s loot!
Recently, on certain planes, they’ve opened membership to non-kobolds in unionized dungeons in a mirror of the real-world IWW’s philosophy of industrial (rather than trade) unionism. There’s been some debate about forming a new union that’s more inclusively-named, but it hasn’t gotten very far.
In-game, unionized dungeons tend to be much more organized, drawing inspiration from the old story about Tucker’s Kobolds. The kobolds are armed and armored and show strong teamwork and planning, making for a real tactical challenge for adventurers who think they can just mow through. They are, however, very open to diplomacy, and have been known to work with adventurers on occasion, especially against bourgeois dragons who attempt to enslave them.
Mate, that’s glorious!
Haha glad you like it! Feel free to steal it for your own, I see it as them opening another local hall :)
I don’t have any campaigns of my own running yet, but I did discuss it with people at my table. So who knows…
The key to that is not going there ever.
I literally ran this for my group just now.
Background was a cave system with very limited resources (previously few dead bodies to spare) and the Lich was both rather low on the power scale and Artificer-themed (so no "just spellcasting the party to death) and a Kobold.
So he fought/thought more like an engineer, not a powerful necromancer.
Highlights included:
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Lair filled with Carbon Monoxide (I let the party notice symptoms and retreat, it was more of an area dental tool than a trap)
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freezing the flooded exit tunnel so the party had to tunnel through ice, making them vulnerable to an ambush
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installing an artifact that would flash-freeze said flooded tunnel with the party inside
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a “main entry” labyrinth to the lair that was rigged to collapse
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a side entry with a hidden, massive door that tried to crush the party and did manage to separate them
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one-time sigils that would create a zone of Web, Darkness and, again, flash-freeze the intruders (and the undead defenders delaying them)
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a remote body with his true body walled off in a tunnel behind the wall it can escape even if it loses
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a few, highly upgraded undead
area dental tool
Lmao
Seriously though I love your ideas. This is what really frustrates me about high level play. At that point your enemies aren’t only powerful they tend to be incredibly intelligent. If you play your liches and dragons smart the party shouldn’t even stand a chance unless they are overwhelmingly powerful or happen to catch the enemy way off guard.
Or perhaps I’m just not clever enough to make that work lol.
I’m not even your player and I already hate it, you glorious bastard!
If the players knew that carbon monoxide is flammable it could have played out quite differently.
My players loved and hated it both, but made it through without any deaths (a few death saves, though) and even got the Lich proper.
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Hot take: if you as a DM pull something like this but aren’t otherwise running a “survival” campaign with enforcement of other environment-related rules like encumberance and starvation, you’re a jerk.
You can drop lots of hints, a perception check to notice the flame of their torches has diminished and is threatening to be extinguished. They start making con saves every 2 minutes, if they fail they get dizzy, subsequent failed saves cause headaches, then vomiting. Give them heal or wisdom checks for a chance to determine what’s happening. After 3 failed checks you use the rules for holding your breath and party members with the lowest constitution begin to lose consciousness. Seems fair
I don’t think a potentially deadly concentration of carbon monoxide would displace enough oxygen for a flame to go out. The deadly part is that it makes your red blood cells useless once it binds to them.
No way would it be enough to dim a fire, because CO floats. You’re either out of range entirely because the ceiling is too high, or you’re screwed enough to have already noticed.
The deadly part is carbon monoxide is flammable. If the party is in any sort of situation requiring torches or any one of them takes any action that creates an unlucky spark, you will never stop finding the body.
Which makes it a questionably intelligent plan for a lich.
posted-as-written the undead fucker has filled it’s lair with carbon monoxide. not tainted the air supply, not attempted to poison the player, the lich has FILLED it’s lair.
No torchy, no respiration and woozy falling asleep, this is open the door OH FUCK GASP DIE
So tell me then, what would make sense? How to implement this intelligently into an encounter?
With named poison gases one would find irl, there really isn’t a lot available that would meet the requirements. 99.9% are too volatile either to open flame or the presence of oxygen, have a very strong smell and/or obvious color that one probably couldn’t explain away by blaming it on the tinted glass of a nearby lamp.
Or they cause immediate symptoms that the party would be far too damaged by to doubt what’s happening (blindness, lung damage requiring immediate medical attention, etc.), or the symptoms don’t show up for 3+ days or require months of exposure. At which point, I consider any lich really wouldn’t bother doing that on purpose because who’s it going to slow down? It would be more of an accidental environmental feature like radon that would leave the surviving players lingeringly convalescent just to piss them off.
For something so non-reactive it poses no danger to the big bad, with immediate symptoms that are still deadly while being understated enough that an adventurer might brush them off…it would more or less have to be mostly or entirely inert, I feel like. Nitrogen, argon, and krypton are all heavier than air, inflammable, unnoticeable, and all easily made through an identical process at differing temperatures, with krypton additionally exhibiting a strong anesthetic effect.
A study of nitrogen gas as a replacement in fire extinguishers doused varying types of fires in 11-71 seconds. So your torch would go out, yes, which would be really cool. With this one, at least, it also seems to have a habit of reigniting when you leave. Fun!
However, my main concern with this would be that because all you’re doing then is displacing the air with something your body doesn’t even notice. There will be progressive symptoms as one approaches the source: fatigue, a feeling either of panic or drunken euphoria, dimmed vision, dizziness/incoordination, nausea and vomiting, confusion and hallucinations that may make them roll at a disadvantage to address any of these things.
And then you fall over and die. These things kick in very fast irl and kill even faster. As in, unconscious in half a minute and brain-dead in ten minutes or less. This would obviously be unfair to the party. Your light would go and then you go.
The two thresholds are very close for my liking, making the question in my eyes how fast they would notice anything is wrong before they had to grab a new character sheet. You’d have to fudge reality a bit if you wanted to make this even a little bit not bullshit.
And in a setting where the lich has intentionally depleted an area entirely of oxygen? We already have places like that. Pluto’s Gate in Turkey emits a steady stream of CO2 that pools on the floor of the cave in such strong concentrations that anything passing the threshold at the wrong time of day is dead unless it can hold its breath. You didn’t get a warning beyond what the locals would tell you and probably all the corpses. In roman times, they sold birds for the tourists to toss in. You’re going to have to make something up.
A great answer, thank you. A hall of nitrogen horrors does seem like a perfect entrance to a lich’s underground castle. Perhaps an ‘isekaid’ lich from our world would do exactly that (reminds me of Nazarick). Or a different but very similar element could be less violent in the way it affects living beings but still dangerous for a 1h+ descent. Interesting!
Yea, I think Nitrogen would be a safer choice (for a Lich) than CO.
Just permanently filling their enclosed lair with an inert gas that displaces oxygen would be a strong deterrent.
Maybe a bit extreme for a rust inhibitor, but lichdom is also an extreme “solution”.Edit: hold on… THE Nepenthe? Who likes yarn and cats? What a nice surprise running into you here
Edit: hold on… THE Nepenthe? Who likes yarn and cats? What a nice surprise running into you here
I KNEW IT WAS YOU. I was just debating saying something in the discord! Both a pleasant and hilarious surprise
I’m thinking for what they want, something inert would be a good deal, yeah. Just nitrogen can be made in quantity pretty easily, would displace the air enough to put out a fire, and cause disorientation, possibly nausea. Main problem is, we would be talking brain death in a little over a minute and that may not be enough time if the party is dnd stupid. A TPK in the span of a couple breaths, because without the CO2 you wouldn’t understand what’s going on until someone noticed the torches, and they may be too out of it by the time that they do.
Kinda wanna go through a list, now, to see if there’s anything heavier than air that’s entirely or quickly becomes odorless, has more pronounced symptoms than “confusion,” and wouldn’t kill quite so fast, but I’m not entirely convinced because of…how necessary breathing is. The rotten egg smell of hydrogen sulfide dissipates very quickly into nothing, but one breath is enough to kill you and that isn’t hyperbole.
All that would, of course, be assuming we’re playing by irl rules despite the whole place being built by a zombie wizard.
Oh for sure it’s an absolutely terrible idea for an actual game because it’s kind of a cheap TPK, it’s just a great idea for of you ever become an actual lich.
That’s just poison gas that has no color or odor. That’s standard dnd shit. CO has detectable symptoms.
Now you want to be evil? CO2 just feels like shortness of breath. Want to be diabolical? Very high nitrogen has no symptoms. You just die.
More info for those interested,
The main symptom of CO poisoning is sleepiness. By the time you realise it you’re just thinking to yourself I’m tired and I’m going to take a quick nap, then you never wake up.
CO2 poisoning is easy to spot because you’re suddenly very breathless and hyperventilating for air.
This is because our respiration is controlled by the percentage of CO2 in our blood. Not by the amount of oxygen. So we actually don’t react to most gases, we just KO and thats it. If no one removes you from that area, you’re a goner.
I think you’d know something is off here a bit faster - evil sorcerer is filling the crypt with CO. You immediately will be unable to draw breath, there will be no oxygen in the air. Carbon Monoxide poisoning occurs when there’s still oxygen to breathe, it’s just got lots of CO… unlike Nitrogen when you can resperate and attempt to breath until you fall over dead, your lungs don’t want to take in CO. It won’t be gradual, there’s literally nothing to breathe.
While I appreciate we’re discussing hypothetical DND scenarios, I’d just like to take a moment to highlight the dangers as it’s an actual risk we deal with in reality. (Cars and heating systems)
CO is a very dangerous gas for a reason. Its known as a silent killer because while there are symptoms, it’s mild and easily mistaken for other medical issues. Its not uncommon to be wrongly diagnosed by medical professionals. CO works by binding to hemoglobin 200% stronger than oxygen and stays bound for hours. So unlike nitrogen hypoxia, where once you brought back to a high oxygen environment, you will start recovering, CO poisoning remains. Even a 100% Oxygen environment will not in itself save you from severe poisoning because the CO is so strongly bound to your blood that oxygen cannot displace it.
Anyways in a (near 100%) flooded environment, the players are already dead when they feel the symptoms. Once CO is bound to their blood stream the only treatment is hyperbaric oxygen therapy.
Good to know information:
0-9 ppm CO: no health risk; normal CO levels in air. 10-29 ppm CO: problems over long-term exposure; chronic problems such as headaches, nausea 30-35 ppm CO: flu-like symptoms begin to develop, especially among the young and the elderly. 36-99 ppm CO: flu-like symptoms among all; nausea, headaches, fatigue or drowsiness, vomiting.
100+ ppm CO: severe symptoms; confusion, intense headaches; ultimately brain damage, coma, and/or death, especially at levels 300-400+ ppm
Ok, now what’s the result for CO 1,000,000ppm?
That’s what the Lich has done. It has filled the space with CO.
I’d say you’re dead once you take a breath of that. It’s probably going to feel like you’re breathing 100% nitrogen because your body will think it’s breathing out CO2 like normal. You’ll get weak really fast since you’re deprived of oxygen and then you just die because your blood cells are ruined.
CO has detectable symptoms.
Not on the body. Which is why it is high in the statistics of cause of death for farmers. Silo gases are dangerous, heavier than air too.
Btw, candle doesn’t help: you’re dead before the flame extinguishes.
Not symptoms you notice until it’s too late.
Also, that dungeon better be pitch fuckin’ black. Torches ain’t gonna work with that shit lol
Finally, the light spell is useful
And it’s even better because all the characters will start hallucinating before they figure out what’s going on!
The nastiest thing about lack of oxygen is that the first effect is losing your ability to tell that anything is wrong with you. The perfect killer.
wistful sigh
That sounds like the way to go.
sigh I wish that were me
In most cases they probably won’t even notice what’s going on, assuming they continue deeper down the dungeon they’ll pass out before they figure out it’s monoxide poisoning (if that concept is even known to anyone in the party)
Science, lich!
How would you deal with this in 5e? From spells I’m seeing you’ve really only got water breathing and air bubble from spell jammer. It’s a pretty classic dnd trope so I’m surprised there’s no solution.
The Necklace of Adaptation is probably the best option. It’s an uncommon magical item from the DMG that requires attunement.
While wearing this necklace, you can breathe normally in any environment, and you have advantage on saving throws made against harmful gases and vapors (such as cloudkill and stinking cloud effects, inhaled poisons, and the breath weapons of some dragons).
Poison immunity (monk), not breathing (various races), blasting open the entrances to increase ventilation
I’d argue that even with poison immunity, you’d need to worry about the presumed lack of oxygen.
Tortle Monk - immune to poison, ac17 at first level, and can hold breath over an hour.
Poison immunity wouldn’t help, at best it would prevent the panic feeling and hallucinations caused by breathing in CO, but the lack of oxygen would still kill you.
Gust of Wind would probably work well too, at least for a good chunk of the dungeon. 60ft long 10ft wide for 1m. That’s going to be a lot of airflow. It depends on if there’s a constant source of carbon monoxide or if it’s a limited amount that can be cleared eventually.
In Pathfinder, Air Bubble and Life Bubble would be the best choices.
Carbon monoxide is also flammable, so if they brought a torch into the room it should have worked itself out.
“The overwhelming stench of century old farts fills the air.” (DC30 Con Save)
Vaguely reminiscent of the cursed mine my PCs will learn about someday. A simple mine, extracting silver, with a large amount of pitchblende. The corporate mine owners want to increase output from the mine, but miners experience curse-like symptoms when they stay there too long. It’s a mystery why this cave in particular causes miners to feel fatigued at first, ending up with lesions on the skin and vomiting blood. Remove Curse doesn’t seem to help at all, but for some reason a simple Lesser Restoration is enough to end the symptoms…
I actually want an undead dungeon filled with toxic fumes now.
“It’s okay, I brought a Bag of Holding full of air with me. Now I’ll just put it on my head, and…”
Blind, works for ten minutes.
Lol
Life bubble not a spell in DnD?
Not in 5e; it dumbs down a lot of it’s spells/casting.
If a DM pulled this and was really hard nosed, I would be pulling out my 3.5e books. All the really good planar/space stuff belongs to this gen.
Ah yeah. Too used to pathfinder/3.5, so this would be an annoyance but as long as prep life bubble or have an oracle you’re fine lol. Not a spell that comes up a TON unless you’re going underground pretty deep.
Sounds like y’all don’t know about chickens.
