Expanding on something I wrote for Dungeon Vault Magazine back in issue 32 this is a new class for Shadowdark with its own spell list. This is a class that might go with a whole setting I am considering putting together.
If I am feeling productive twice in one week there might also be an Old School Essentials/B/X version of this class as well but don't hold your breath on that one.
Plaguemancer
Indulgers of hubris who seek to bend the pestilences of the world to their own will in the search for power.
Weapons: Club, Mace, Staff or Warhammer.
Armor: Leather armor, shields.
Hit Dice: D6
Languages: You know Diabolic.
Turn Diseased. You know the Turn Diseased spell.
Master. You draw your power from one of the demon princes of the unclean world. Plaguemancers who offend or fail to follow the demands of their master not only lose their abilities but may also face further punishment.
Spellcasting. You can cast Plaguemancer spells you know.
Plaguemancers gain spells at the same rate as a cleric of equivalent level.
You use your Constitution score to cast plaguemancer spells. The DC is 10 + the spell’s tier. If you fail a spellcasting check, you can’t cast that spell again until you complete a long rest.
Plaguemancer Talents
2d6 Effect
2 Gain advantage on casting one spell you know
3-6 +1 to melee attacks
7-9 +1 to plaguemancer spellcasting checks
10-11 +2 to Constitution score or +1 to any two other scores
12 Choose one option from the table
Plaguemancer titles
Level Lawful Chaotic Neutral
1-2 Tainted Unclean Moulder
3-4 Bearer Leech Rotbringer
5-6 Host Corruptor Putrifier
7-8 Outcast Defiler Despoiler
9-10 Forsaken Plaguefather Master of decay
Spells
Tier 1
Chattering Children
Conduit of Corruption
Detect Disease
Protection from Disease
Putrefy Food and Water
Turn Diseased
Tier 2
Aura of Sickness
Bane
Cloud of Stench
Decay
Fever Spike
Mass of Maggots
Tier 3
Bile Spray
Cloak of Flies
Command Sick
Disease
Mind Worm
Mold Touch
Tier 4
Blight
Dark Communion
Drain Life
Plague Curse
Swarm
Unclean Wings
Tier 5
Destroy Food
Helplessness
Infect
Insect Plague
Writhing Agony
Wither
Aura of Sickness
Tier 2
Duration: Focus
Range: Close
A feeling of ill health permeates around you. Creatures in range have a -2 penalty to attack you.
Bane
Tier 2
Duration: 5 rounds
Range: Touch
One creature you touch gains disadvantage on one ability check or attack roll of your choice during the duration of the spell. After that, the spell ends.
Bile Spray
Tier 3, wizard
Duration: Instant
Range: Close
Consuming the moldy bread causes you to spew forth a torrent of bile, pus and maggots.
Creatures in the area who have fewer hit dice than your level lose their turn, gagging and attempting to clean themselves.
Blight
Tier 4
Duration: Instant
Range: Touch
Destroys plants or plant based creatures with lower HD than you.
Chattering Children
Tier 1
Duration: 1 hour
Range: Self
Swallowing a handful of fly larvae you regurgitate them as a swarm of buzzing flies that will carry a single message of up to twenty five words. The flies will travel a distance of up to five miles over an hour then fall dead to the floor if they have not found the recipient in that time.
Cloak of Flies
Tier 3
Duration: 10 rounds
Range: Close
Buzzing flies swarm around you, obscuring you and any allies from the view of others.
Cloud of Stench
Tier 2
Duration: 5 rounds
Range: Far
A near-sized cloud of stench apporates into existence. A creature inside the cloud must make a Constitution check or spend their turn retreating.
Command Sick
Tier 3
Duration: Instant
Range: Far
Infected, sick or diseased creatures in range must follow your commands. You can command creatures whose hit dice are less than or equal to half your level rounded down (minimum 1).
Conduit of Corruption
Tier 1
Duration: Focus
Range: Touch
You absorb the disease or sickness of the creature touched without suffering any of the effects and you may pass the disease on to another creature you touch if they fail a constitution check against your spellcasting check.
If your focus is broken and the spell ends while the disease still inhabits your body then you are now afflicted with the disease.
Dark Communion
Tier 4
Duration: Instant
Range: Self
Beseeching your master for assistance you may ask three questions. The GM will answer “Yes” or “No” based on your master's desires.
Decay
Tier 2
Duration: Instant
Range: Touch
One item made of natural materials such as wood or leather quickly decays to the point of failure. The item may be no larger than a single door
Destroy Food
Tier 5
Duration: Instant
All food within range is destroyed or rendered inedible.
Detect Disease
Tier 1
Duration: Focus
Range: Near
You can sense if creatures in range are infected by sickness or disease, if so by which maladies and how they might be cured.
Disease
Tier 3
Duration: Instant
Range: Far
One creature you can see is infected with a disease of your choice.
Drain Life
Tier 4
Duration: Instant
Range: Touch
You siphon 2d6 points from a creature you touch, harming them and healing yourself.
Fever Spike
Tier 2
Duration: Instant
Range: Close
You cause the temperature in the body of a creature to rise dramatically. It takes 1d6 damage.
Helplessness
Tier 5
Duration: 10 rounds
Range: Far
Within a near-sized circle no creature may gain the benefit of any healing for the duration of the spell.
Infect
Tier 5
Duration: Instant
Range: Far
All creatures you can see within range are infected by a disease of your choice.
Insect Plague
Tier 5
Duration: Concentration
Range: Far
When cast above ground a plague of insects descends on a location of your choice. You can move the swarm and see through their eyes. Creatures of level 2 or less are driven away, any spellcasting checks made inside a swarm are done so at disadvantage.
Mass of Maggots
Tier 2
Duration: 10 rounds
Range: Self
Squashing a putrid maggot between your fingers you and your gear turn into a swarm of wriggling maggots for the spell’s duration.
You can move and pass through any gap a maggot could. You can sense the terrain and any movement around you out to a near distance.
You can’t cast spells while in this form.
Mind Worm
Tier 3
Duration: Instant
Range: Touch
You place a worm so it can wriggle inside the ear of a living being. The spell has the same effect and stipulations as the Speak With Dead spell.
Mold Touch
Tier 3
Duration: Instant
Range: Close
You blow spores into the face of a creature causing 1d6 damage and blinding them until they succeed on a Constitution check opposed by your spellcasting check.
Plague Curse
Tier 4
Duration: Instant
Range: Touch
One creature you touch unknowingly becomes the carrier of a disease of your choice. They will infect 2d6 people before succumbing to the disease themselves.
Protection from Disease
Tier 1
Duration: Focus
Range: Self
For the spell’s duration, all infected, sick or diseased creatures have disadvantage on attack rolls and hostile spellcasting checks against you.
Putrefy Food and Water
Tier 1
Duration: Instant
Range: Close
Either 6 quarts of liquid, one ration or unpreserved food sufficient in quantity for 12 people is putrefied.
Swarm
Tier 4
Duration: 5 rounds
Range: Far
A swarm of bugs erupts from the ground engulfing creatures in a near-sized cube. Creatures in the cube must succeed on a Dexterity check opposed by a spell casting check to free themselves.
Turn Infected
Tier 1
Duration: Instant
Range: Far
Works as the Turn Undead spell except on infected, diseased or sick creatures.
Unclean Wings
Tier 4
Duration: Focus
Range: Self
Foul wings sprout from your back. You can fly a close distance each round and can hover in place.
Writhing Agony
Tier 5
Duration: 5 rounds
Range: Close
A creature whose hit dice are less than or equal to your level writhes in agony, they are unable to move or act for the duration of the spell.
Wither
Tier 5
Duration: Instant
Range: Touch
You touch a living creature aging it to within the final years of its life reducing it to one hit dice. This spell may only be case on creatures whose hit dice are less than or equal to your level.