D&D 5E Help me develop a disease

[Charlaquin]

For an upcoming campaign I at building, I want the players to deal with a rapidly-spreading Plague. Specifically, one caused by exposure to Aboleth mucus. But the disease in the Aboleth’s MM entry advances far too quickly for my purposes. So I want to create a slow-burn version of it.

I know I want the symptoms to start by resembling dehydration. Then after this dehydration advances beyond a certain point, the patient will start developing resperatory complications, probably akin to pneumonia. Only in the final stages of the disease will the patient’s skin start to become pale and eventually translucent, and to secrete the same mucus that carries the disease. Ultimately the patient becomes unable to breathe above water. This should develop over the course of a few weeks.

So I need to develop some mechanics for this disease. I’d like it to involve multiple Constitution saving throws so that it can be slowed, but not cured, by rest (as the downtime action). Probably DC14 as the disease in the Aboleth’s stat block. I could see dehydration being modeled with Exhaustion levels. And in the final stages it can use the mechanics straight from the Aboleth stats, with the inability to regain hit points and damage at regular intervals unless water is applied to the skin. The trouble is, I’m not sure what the intermediate stages should look like mechanically, or how it should advance.

Now, I know I don’t really need Hard-coded mechanics for something like this. Ultimately it will advance at the speed of plot and the symptoms will be what they need to be at the moment. But I’m the kind of DM who likes having rules for these things. It makes them feel more a part of the world to me. So if your advice is just to run the disease as the plot demands, I appreciate the intent behind it, but it’s not what I need. Any ideas or suggestions as to specific mechanics would be a big help.


Thanks in advance!

 

[robus]

Yep definitely the system you implement should have levels as exhaustion does (probably tiers as you want this disease to develop slowly) - so each week the sufferer gains another tier of illness unless they make their saves which could be a daily con save, if they have more successes than failures they don’t drop to the next tier but continue into the next week (and another round of saves). If they succeed they take half the damage, full damage if they fail as usual.

As far as the number tiers I’d suggest following the exhaustion model again. 6 levels and if they reach the last one they die (or turn into an aboleth )

 

[Charlaquin]

Yep definitely the system you implement should have levels as exhaustion does (probably tiers as you want this disease to develop slowly) - so each week the sufferer gains another tier of illness unless they make their saves which could be a daily con save, if they have more successes than failures they don’t drop to the next tier but continue into the next week (and another round of saves). If they succeed they take half the damage, full damage if they fail as usual.

As far as the number tiers I’d suggest following the exhaustion model again. 6 levels and if they reach the last one they die (or turn into an aboleth )

So separate the stages of the disease into levels like exhaustion, and gain levels of the disease instead of levels of exhaustion for failed saves? That’s a really good idea, I was struggling trying to fit Exhaustion into the effects of the disease somehow, but this would make a lot more sense.

So maybe it functions similarly to dehydration - drink X amount of water per day or gain a level of the disease. Drinking half the daily requirement allows you to make a save to avoid the level. Then as it advances you start picking up more symptoms and the daily water requirement increases.

 

[Gardens & Goblins]

...we can share my toothbrush?

 

[robus]

So maybe it functions similarly to dehydration - drink X amount of water per day or gain a level of the disease. Drinking half the daily requirement allows you to make a save to avoid the level. Then as it advances you start picking up more symptoms and the daily water requirement increases.

I dunno about making it that easy to overcome the effects of the disease, this thing should be a visceral threat? I would say that people have a terrible thirst and that thirst just gets worse along with the other effects. So that when you’re at level 5 you’re kind of producing more water than you can physically consume...

People might believe that drinking water helps you but really it’s your bodies own ability to resist the disease that is helping.

Lesser restorations reduces the effect by one level. Great restoration cures the disease entirely?.

 

[pukunui]

The best way to develop a disease is to expose yourself to it ...

 

[Charlaquin]

I dunno about making it that easy to overcome the effects of the disease, this thing should be a visceral threat? I would say that people have a terrible thirst and that thirst just gets worse along with the other effects. So that when you’re at level 5 you’re kind of producing more water than you can physically consume...

People might believe that drinking water helps you but really it’s your bodies own ability to resist the disease that is helping.

Good points. But that does leave me to figure out the mechanism for advancement. I guess it could be as simple as a con save at certain intervals.

Lesser restorations reduces the effect by one level. Great restoration cures the disease entirely?.

I definitely want it to only be curable by 6th level magic or higher, as the disease from the Aboleth stat block, at least in the later stages if not earlier. But I do like the idea of lower-level magic being able to reduce the level. This is kind of the lines I was thinking along:

1: The creature’s daily water requirements are doubled.
2: ?
3: The disease cannot be cured except by magic of 6th level or higher.
4: The creature can’t regain hit points unless it’s underwater.
5: The creature takes 1d12 acid damage every 10 minutes unless water is applied to its skin.
6: The creature can only breathe underwater.

I suppose I could bump everything below 2 up a level and make 6 death, or becoming a thrall to the Aboleth that the disease originated from, or something along those lines.

 

[MechaTarrasque]

Extreme dehydration appears to be represented by necrotic damage in 5e, so I would have the infected make a con save at the end of every long/short break, or else take 1dx necrotic damage, where x increases as the # of days increase.

 

[robus]

Good points. But that does leave me to figure out the mechanism for advancement. I guess it could be as simple as a con save at certain intervals.

Yeah that's why I suggested the daily con save (probably done in the morning as that is when people see it they "make it through the night" ) - 7 con saves per week. If you make the majority you remain at the current level, if you fail the majority you sink deeper into the disease. I guess you could also say that if you make all the con saves (7 days straight) you shake off a level of disease.

I definitely want it to only be curable by 6th level magic or higher, as the disease from the Aboleth stat block, at least in the later stages if not earlier. But I do like the idea of lower-level magic being able to reduce the level. This is kind of the lines I was thinking along:

1: The creature’s daily water requirements are doubled.
2: ?
3: The disease cannot be cured except by magic of 6th level or higher.
4: The creature can’t regain hit points unless it’s underwater.
5: The creature takes 1d12 acid damage every 10 minutes unless water is applied to its skin.
6: The creature can only breathe underwater.

I suppose I could bump everything below 2 up a level and make 6 death, or becoming a thrall to the Aboleth that the disease originated from, or something along those lines.

Do you have physical manifestations for each of these levels? For example:

1. Mouth feels continually dry. Rasping cough (to spread the spores )
2. Bloodshot eyes and bloody nose (from dried out mucus membranes) and painful cough with blood in sputum.
3. ??
4. Skin starts painfully flaking off like fish scales
5. Gills appear on the creatures neck below the ears.

I'm not seeing how 5 comes after 4 if the creature is underwater than they're already getting water applied to its skin?

 

[Charlaquin]

Yeah that's why I suggested the daily con save (probably done in the morning as that is when people see it they "make it through the night" ) - 7 con saves per week. If you make the majority you remain at the current level, if you fail the majority you sink deeper into the disease. I guess you could also say that if you make all the con saves (7 days straight) you shake off a level of disease.

Tracking the number of save successes and failures over the course of the week sounds like a lot of bookkeeping. Maybe successes and failures give cumulative bonuses and penalties to the next save, and when you get up to, say, +/-5, you move up or down a step respectively?

Do you have physical manifestations for each of these levels? For example:

1. Mouth feels continually dry. Rasping cough (to spread the spores )
2. Bloodshot eyes and bloody nose (from dried out mucus membranes) and painful cough with blood in sputum.
3. ??
4. Skin starts painfully flaking off like fish scales
5. Gills appear on the creatures neck below the ears.

These are good! You could bump the dried out mucus membranes by one and add hyper-secretion above it.

I'm not seeing how 5 comes after 4 if the creature is underwater than they're already getting water applied to its skin?

The way I was thinking about it was that most people won’t even realize how 4 works before going up to 5. None of the previous symptoms cause HP loss, and being unable to recover HO isn’t a terribly uncommon disease symptom. If they even realize rest isn’t helping them recover from injuries, most people’s first instinct isn’t going to be to sleep in a pool of water. And if they do figure it out somehow, it gives them a better chance of surviving stage 5, which is incredibly brutal if you don’t figure out almost immediately that moistening the skin is the key to avoiding the damage.

But you might be right that damage without regular moisture -> can’t heal unless underwater is a more natural progression than the other way around.