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July 1, 2010 / JBencomo

Getting your players sick. What Diseases can bring to your campaign

A DM tool box is filled with an incredible array of items (going from mechanics to fluff) whose ultimate goal is to provide a fun, interesting, compelling and challenging playground. That being said, Diseases fall into the “under used” category in most DM’s répertoire even though they provide a unique feature other challenges (encounters, traps, etc) do not: lasting threat.

When your players hear “roll initiative” they might fell an  impending threat, until the last enemy hits the ground. Yes they will feel threatened when the skill dices start bouncing on the table to deactivate the trap, but once that *click* sounds, for better or worse, the threat will end and relief will come. But maybe that’s not your intention at all… perhaps you need the party to be concern about their well being, even (specially) when they decide is time for an extended rest… they just might wake up worse… That’s when Diseases in 4th edition come in.

Diseases & 4th Edition

The mechanics for Diseases in 4th edition are rather simplistic, and are described in the DMG page 49; First stage is infection, this can happen in a variety of ways (being attacked by a monsters with a [Disease] keyword attack, exposure through environmental effects, food & drinks, etc) in the case of a monster attack, the player does a saving throw at the end of the encounter, if he fails, he gets infected; in other types of infection the Disease makes an attack against a players defense, in any case, at the point you get infected you suffer the Initial Effect of the Disease. Then comes the Disease Track, here the player makes Endurance checks at the end of every extended rest against 2 target DC’s; beat both and you improve, beat the lower and you maintain your condition, fail to beat both and you get worse, this track continues until you get cured, or you get worse enough to suffer the Disease Final State.

More than one way

There is really no limitation on how a good DM can introduce Diseases to their players, always remember that D&D is a fantasy universe, where some limitations may not apply. Taking that into consideration here are two groups where we can classify contraction methods:

Monsters Attacks: perhaps the most known, some monsters like the Slaad, Gnoll and Rot Grub have attacks with the [Disease] keyword, any player that gets hit by such attack must make a saving throw at the end of the encounter, if he fails he gets infected, not really much else here.

Other Exposure: Here is where Diseases get time to shine as argument and plot twist, and there is really no limitation on how you can do it, perhaps a plague in the town your players just arrived (ah  neverwinter nights….), infested water from a river, even an innocent *cough* from a town child who ends up being a infectious changeling, there is really no restriction into how many interesting ways you can create to use Diseases in your campaign.

There is a time and place for everything…. even to get sick.

This is the really tricky part on Diseases, make your party sick in the middle of an already hard dungeon and you might be facing a TPK, infect them right next to the town temple and they’ll just go get healed right away like it never even happened. But if you take this in consideration and account for it, Diseases can really turn a somewhat mundane task into a survival/threatening challenge. Imagine a Skill challenge where your players have to spend a few days going trough a swamp, want to spice things up? make one or two players sick and now a plane task of rolling for skills has them at their sits edges… if they don’t get out of the swamp soon, some of the players might not make it in time.

Calling Dr. Mario to the Emergency room…

Be really clear and specific about what you want your Disease pose to the party, is it a minor setback? a plot challenge they have to endure? something that could really kill them? after you have that sorted out, plan exit strategies. Does the party have the means to cure such disease (Remove Disease ritual) or do you have to put some NPC to help them? may be they need to accomplish a quest to get healed? do you want the Disease be treatable at all?.

A common believe about Diseases is that after 6th level they are easily removed through a ritual and they pose no real threat, this again depends on the DM. Personally I’m against saying “Your ritual doesn’t work because… ehm, magic” but if you are introducing a plot related disease you might need the party not to be able to use it, be creative; the disease might come from a object they MUST carry as a quest item, disabling the ritual, the disease could be magical in origin altering the ritual propose (instead of healing you can only transfer the disease to another player, perhaps one who is more resilient) what I’m trying to say here is do not negate a player the chance to use something they have, rather be creative to reward him while maintaining your plot needs.

I also would want to point out that the Remove Disease ritual is really well done, and carries an inherent risk for the person who’s being healed, so if your Disease falls into the “minor setback” category, go ahead and make it possible to use the ritual, if not, then consider the consequences of such a diseases and how your party can get out of them (and if the’ll make it that far)

Bio Organic Weapons 101

Another point against Diseases in 4th Edition is their scarcity. There are around 25 different diseases combining DMG, MM1, MM2 and MM3 and most of them are the Monster Attack type, that’s why I came up with a mini guide to help you customize and design your own:

1.- Set the fluff:

For me its easy to think about the fluff first, if you first determine the situation/setting where you want to introduce your disease it becomes more easy laying out the rest.

2.- Set Mechanics:

A) Level and Difficulty: here you need to establish what you need your Disease to accomplish, and set the DCs according to your party levels and how easy/hard you want it to be for them to improve/get worse, then determine the attack bonus of the Disease to see how likely/unlikely it is for the it to actually infect a player if that level.

B) Effects: Diseases effects range from a great variety: losing healing surges, regain less hit points from heals, impose status effect, vulnerabilities, effects that trigger on bloodies, penalty to attack or defenses, etc. So there is really a lot of options here.

Keep in mind that you should balance the level/difficulty with the effects of the disease, a really easy to infect disease with low effects is ok, a low provability of infection Disease with harder and more dangerous effects is also ok. A High rate infection disease with hard saving difficulty and really bad effect is just boring and dangerous.

I strongly recommend you look for Diseases of similar level when appointing the numbers of your own, it also help to look the attack bonus of several monsters of the same level when determining the attack bonus and target DCs by level in DMG, this way you prevent doing something imbalanced. Finally go back to the fluff for your Disease and check if all adds up, take special attention to relate the origin of the disease with the defense it target and the effects it causes.

A few Examples:

To sum up I want to let here a few example of Diseases I find interesting in order to give you an idea and inspiration to create your own.

Sun Sickness Level 2
The sun’s punishing rays leech vitality from your body
Attack: Level +4 Vs Fortitude
Endurance improve DC 17, maintain DC 13, Worsen DC 12
* The Target is cured
* Initial Effect: The target loses one healing surge or hit points
equal to the Target’s surge value, the hit points or healing surge
cannot be regained until the target is cured
* The target takes a -2 penalty to all attack rolls and defenses
* The target is slowed and weakened
* Final State: the target dies

(From D&D encounters Season 2 – Dark Sun)

Cackle Fever Level 12
The symptoms of cackle fever include high fever, disorientation and
frequent bouts of hideous laughter.
Attack: +16 Vs Fortitude
Endurance improve DC 22, maintain DC 17, Worsen DC 16
*The Target is cured
*Initial Effect: The target begins each day with no action
points. Each time the target becomes bloodied, it laughs
uncontrollably and is dazed (save ends). Both of these effects
apply until the target is cured.
*The target cannot gain or use action points.
*Final State: the target is catatonic and ubable to take any actions

(From Dungeon Masters guide)

Screaming Scalepox Level 15
Dark, scaly flesh spreads over the victim’s body, wracking it with
excruciating pain
Attack: +18 Vs Fortitude
Endurance improve DC 23, maintain DC 18, Worsen DC 17
*The Target is cured
*Initial Effect: The target loses a healing surge that it cannot
regain until cured of the disease
*The target takes a -2 penalty to all defenses and loses two healing
surges that it cannot regain until cured of the disease
*Final State: the target recovers from the effect of screaming
scalepox but becomes a loyal servant of Demogorgon.

(From Demonomicon Excerpts)

As a player i haven’t been in a campaign where Diseases played a part, nevertheless I’m planning to introduce them in my campaign recognizing the unique features they bring to the game. So what about you? Have you ever being or DM a campaign that uses Diseases? how was it?



Leave a Comment
  1. Dave Williams / Jul 1 2010 10:41 pm

    We recently had our healer (Warlord) come down with a case of pregnancy…ok I don’t know what the actual disease was but he got it from a Skald. We ended up doing triage in the field via heal checks and then rushing back to town.

    That has to be the first time I’ve seen a disease used by the DM. After reading your post however it could make for some very interesting plot lines, or power character “fixes”

    • DM Baloo / Jul 1 2010 10:51 pm

      Lol that had to be fun (and scary for the warlord). Yeah right now I’m playing with some Level 2 Diseases I want to trow to my new players. I want to see their faces when they have to escort a sick npc from a town to another while getting sick, may be a skill challenge with a combat in between hehe

  2. Tourq / Jul 1 2010 11:31 pm

    I like the idea of diseases, but I think that they work a lot better against mature players. I’ve played with some who would say, “So DM, you like to win at all costs… way to be a cheater.” While others have said, “I’m blind and puking? Bring it!”


    • DM Baloo / Jul 1 2010 11:39 pm

      “I’m blind and puking? Bring it!” LOOOL thats the kind of player i like, but i get your point, and the problem is, Diseases are not that common, so they might seem to the unexperienced player a “trick” from the DM. Really is more important in those cases that the player understand the DM is not the enemy and that we do not win if (when) we kill players.

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