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
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!
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!