Contagion Spell Guide DnD 5e

A creeping, lingering sickness that attacks the eyes, the lungs, the heart. It leaves you weakened, wracked by painful coughs, bleeding through your skin. The first waves of nausea are nothing compared to what comes next — nothing compared to the horrors that await when the contagion has you in its grips. 

Greetings, Dungeon Masters and adventurers! Today we’re going to be talking about Contagion, a 5th-level spell from the school of Necromancy that might just be a contender for Dungeons & Dragons 5e’s grossest magical effect. 

Ick factor aside, Contagion has a lot of potential for the unscrupulous player. Characters can use it as a high-risk, high-reward tool for completely disabling powerful enemies, condemning them to a messy, painful (slimy) doom. We’re going to be taking a look at how this spell works and how players can make the most of this high-risk-reward addition to their spell list. 

What Is Contagion in DnD 5e? 

Contagion is a 5th-level Necromancy spell available to Clerics and Druids. When the caster touches a target (by making a melee spell attack) they afflict it with the poisoned condition and force it to make a series of Constitution saving throws or become diseased for the next seven days. 

Three successful saving throws cure the affliction, but three failed saving throws result in the target spending a week suffering from one of six horrible afflictions. These can range from temporary blindness to “Slimy Doom,” which causes a creature to bleed uncontrollably. 


Your touch inflicts a horrible, lasting disease. Make a melee spell attack against a creature within range. On a hit, the target becomes afflicted with the poisoned condition. 

At the end of each of its turns, the poisoned target makes a Constitution Saving Throw against your Spell Save DC. 

If the target makes three successful saves before rolling three failures, they are no longer poisoned, and the spell ends. If the target fails three saving throws before making three successful saves, they are no longer poisoned but are now affected by one of the diseases listed below. 

The disease is chosen by the caster and lasts for seven days. The disease itself is natural, and therefore any spell, ability, or other effect that removes or mitigates the effects of disease also works on this spell. 

  • Blinding Sickness. Pain grips the creature’s mind, and its eyes turn milky white. The creature has disadvantage on Wisdom checks and Wisdom saving throws and is blinded.
  • Filth Fever. A raging fever sweeps through the creature’s body. The creature has disadvantage on Strength checks, Strength saving throws, and attack rolls that use Strength.
  • Flesh Rot. The creature’s flesh decays. The creature has disadvantage on Charisma checks and vulnerability to all damage.
  • Mindfire. The creature’s mind becomes feverish. The creature has disadvantage on Intelligence checks and Intelligence saving throws, and the creature behaves as if under the effects of the Confusion spell during combat.
  • Seizure. The creature is overcome with shaking. The creature has disadvantage on Dexterity checks, Dexterity saving throws, and attack rolls that use Dexterity.
  • Slimy Doom. The creature begins to bleed uncontrollably. The creature has disadvantage on Constitution checks and Constitution saving throws. In addition, whenever the creature takes damage, it is stunned until the end of its next turn.

Is Contagion a Good Spell?

I don’t think it’s possible to overstate just how devastating this spell can be. From blinding a target to imposing disadvantage on all Strength or Dexterity checks or making an enemy vulnerable to all damage, Contagion might be one of the scariest debuff spells in all of D&D

Any one of the six options could be enough to turn a deadly encounter with the enemy BBEG into a walk in the park, especially options like Slimy Doom, which allows you to functionally perma-stun your enemies. 

Out of the six options, the two most consistently debilitating diseases are probably Flesh Rot (the Charisma check disadvantage is a nice cherry on top of the massive damage vulnerability sundae) and Slimy Doom (the disadvantage on checks and saving throws would be good, but taking literally any damage applying the stunned condition is absolutely disgusting and more or less guarantees victory). 

Even if you don’t end up triggering the disease itself, keeping an enemy poisoned for three to five rounds (giving them disadvantage on Ability Checks and Attack Rolls — not saving throws, sadly) is still worth the price of admission if you’re a higher-level spellcaster (when you have more than a single 5th-level spell to risk each day). 

That being said, Contagion is still the kind of high-risk, high-reward spell that a lot of players won’t want to risk picking up when other, more consistent damage-dealing spells (like Flame Strike and Insect Plague) exist at 5th level, not to mention that powerful single-target debuff, disable, and control spells (like Dispel Evil and Good, and Gaes) are also on the table. 

Taken in a vacuum, there are plenty of reasons not to take Contagion. It’s not a spell that can just be thrown around like Fireball and get consistently good results. 

Firstly, there are more creatures immune to the poisoned condition in the Monster Manual than almost any other condition or damage-type immunity. Because the disease effect of the spell requires the target to be poisoned, a poisoned-immune creature just shrugs off this 5th-level spell like it’s nothing. 

Also, by the time player characters get access to 5th-level spells, full-casters (like clerics and druids) are going to be 9th level. Not only are the kinds of monsters you face at this stage of the game more likely to be immune to different effects and conditions, but the odds of fighting something with a raw Constitution saving throw bonus of 10+ or higher start getting pretty good. Also, at higher levels, spells like Greater Restoration and other disease-ending magical effects are seriously commonplace. 

Therefore, there are relatively few situations where Contagion is a spell you can throw out without planning, preparation, and a little strategic analysis. Pick the right target in the right situation, however, and it’s truly devastating. 

What’s the Best Way To Use Contagion

There are a few things I’d recommend taking into account if you’re considering making Contagion a part of your roster of spells: the campaign, the enemy, and compatible debuffs. 

(Obviously, if you’re playing a cleric or druid, you can swap this spell out again the next day if it doesn’t work for you. This drastically reduces the risk of grabbing Contagion. Still, picking this spell up before the wrong encounter can still hurt pretty badly. If you’re playing a bard who grabs Contagion as part of their Magical Secrets feature or through some other means, make sure you’ve done everything.)

To understand when Contagion is at its most powerful, let’s examine when it’s not the right choice. 

In a hack-and-slash combat-heavy campaign where you fight big, nasty enemies frequently, this spell is almost always going to be wasted.

Unless you’re in a 10+ round boss fight at the conclusion of the campaign (the BBEG probably has a Legendary Resistance to burn on this exact sort of thing anyway), it’s unlikely that you’ll have time to cast the spell, wait three to five turns for the target to fail their three saving throws, and then be able to capitalize on the effects of the disease for more than a couple of rounds before the target either dies from other causes or casts a curative spell on themself. 

For all that it appears to be, this isn’t a combat spell; it’s a murder weapon. 

Imagine a campaign centered around intrigue, murder, plots, and horror — something set in Ravenloft or perhaps one of the newer, less combat-heavy adventures like The Wild Beyond the Witchlight, Candlekeep Mysteries, or Journeys Through the Radiant Citadel. In these kinds of adventures, the NPCs and factions the plates come up against aren’t always perfectly gauged for their level. Sometimes, people are powerful because they command armies or organizations rather than because they’re an Adult Red Dragon with 200 hit points and a CON score of 22. You know, like in real life. 

In these cases, this is where a precise application of Contagion can be deadly. It’s a spell for disabling weaker targets, stopping someone from pursuing you, or preventing them from running away. It’s a tool for instilling fear, blackmailing powerful people, and generally being a bit of a villain. 

Lastly, if and when you do cast Contagion in combat (I personally like to apply the blinding disease to an enemy who likes to escape a lot), it’s important that, in order to maximize your chances of applying a disease, you stack the deck in your favor as much as possible. Some great ways to do this include… 

  • Using a College of Eloquence Bard’s Unsettling Words to force the target to subtract a Bardic Inspiration die result from their next saving throw. 
  • The Mind Sliver cantrip (assuming they fail their Intelligence saving throw) forces the target to subtract 1d4 from their next save. 
  • A wizard from the School of Divination can use one of their Portent dice to potentially swap the result of a saving throw to a lower roll.   

Finding a way to lower the odds of an enemy (especially one with a high Constitution score) from making their saving throws can be a complicated team effort, but an entire adventuring party pooling their resources to ensure a Contagion spell goes off without a hitch is probably one of the few instances in D&D 5e of teamwork actually creating a better result than a bunch of individuals just firing off their own abilities. Again, if you can apply Slimy Doom to the BBEG in the middle of a fight, that battle is over

Final Thoughts

So, if you want to take the time and make the effort to stack the odds in your favor, Contagion can go from being a slightly niche, suboptimal pickup to a bonafide campaign winner. Just make sure you’re casting it in the right situation (aka, where you’re going to have enough time to make it work) on the right enemy (one that’s not immune to being poisoned and doesn’t have a +10 to their Constitution saving throws) and that you and your allies have some other ways of putting your fingers on the scales to help the target fail those saving throws. 

Pull all that off, and Contagion might just become your new favorite way to bring an opponent to their knees.