Eldritch Contamination

THIS IS UNOFFICIAL MATERIAL
These game mechanics are usable in your campaign if your DM allows them but are not refined by final game design and editing. They aren’t officially part of the Dungeons & Dragons game and aren’t permitted in D&D Adventurers League events unless otherwise stated. This content is subject to change at any time between a game session.

Eldritch Contamination

Characters exploring areas of Eldritch Contamination such as those infused by the Spellplague Haze, and arcane radiation emitted by Delerium Crystals may be exposed to eldritch pollutants. These hazards cause a new condition called contamination, which inflicts debilitating symptoms and otherworldly mutations. For player characters, the contamination is measured in multiple levels and an effect can give a creature one or more levels of contamination, as specified in the effect’s description. If an already contaminated creature suffers another effect that causes further contamination, its current level of contamination increases by the amount specified in the effect’s description.
A contaminated character exposed to any source of eldritch contamination, even if no save DC was required from the source, will have to make a contamination save that day when they take a long rest if they did not already gain a contamination rank that day. This contamination save is a Consitution save with a DC equal to their contamination level. On a fail, they gain a contamination level. Upon reaching the maximum contamination level or receiving a number of Mutations higher than a creature's Consitution modifier (minimum of 1), the creature is transformed into a monstrous mutation and is no longer themselves.

(A victim of the eldritch contamination suffering a mutation)

Contamination Levels

A contaminated creature suffers the symptoms from its current level and all lower levels.

Level	Symptoms	Level	Symptoms
1	None	11	Insanity Gained
2	None	12	Reduced Movement -5'
3	Fatigue (Long Rest +1 Hour)	13	Major Visual Deformation
4	None	14	Magical Resistance (All)
5	Minor Visual Deformation	15	Exhaustion (1)
6	None	16	Insanity Gained
7	None	17	Reduced Movement -5'
8	Fatigue (Long Rest +1 Hour)	18	Damage dealt by weapon attacks and spells halved
9	Moderate Visual Deformation	19	Incapacitated
10	Hit points regained by expending hit dice halved.	20	Monstrous Transformation!

Eldritch Mutations

In addition to suffering symptoms, each time a character gains a contamination level, makes a Constitution save at the DC of the current contamination level with a failure resulting in a Mutation! The Game Master may choose the mutation, or determine it randomly by rolling on the Mutations Table. If the result is the same as a mutation affecting the creature, the GM chooses a different one or rolls again. A character that gains more eldritch mutations than their Constitution modifier is immediately a victim of the Monstrous Transformation regardless of the current level of Contamination levels they might possess.

Die Roll	Mutation
1	Rampant Mutation! Roll twice, ignoring this result on subsequent rolls.
2	Rasping. Your vocal cords warp and you may only speak in a halting gurgle. If you have 10 or more contamination levels, your tongue rots and falls out, and you can no longer speak.
3	Wasting. Your fingernails, teeth, and toenails start falling out. 1d4 fall out for each contamination level you have gained.
4	Rotting. Your lips, nose, and ears blacken and wither. If you reach 10 or more contamination levels, they rot and fall off. You can still speak and hear, however.
5	Molting. Painful blisters, welts, and multicolored lesions appear all over your skin, which burst and peel off painfully, exposing the raw sinew underneath. Once you reach 10 contamination levels, your skin entirely sloughs off.
6	Shedding. Each time you gain a contamination level, some of your hair falls out in patches. Once you reach 10 or more contamination levels, all hair on your body completely falls out.
7	Lambent Glow. You emit a dim octarine glow to a range of 10 feet. If you have 10 or more contamination levels, you instead emit bright light to a range of 30 feet.
8	Ocular Tumors. An eyeball opens somewhere on your body for each contamination level you have gained. If you have 10 or more contamination levels, you can see in all directions.
9	Spiked Growths. At the start of each of your turns, you deal 5 (1d10) piercing damage to any creature you are grappling.
10	Aquatic Adaptation. You sprout fish-like fins and gills. You gain a swimming speed equal to your land speed and can breathe underwater. If you have 10 or more contamination levels, you can only breathe underwater; but can hold your breath outside water for up to 1 hour.
11	Amorphous Form. Your bones and organs become gelatinous. You can move through a space as narrow as 6 inches wide without squeezing.
12	Chitinous Skin. Shell-like growths appear all over your body, giving you a +1 bonus to AC. If you have 10 or more contamination levels, this bonus increases to +2.
13	Cyclopean Vision. Your eyes merge into a single central eye which can emit an energy beam as a ranged spell attack using your Intelligence modifier for the attack roll. If it hits, it deals 2d6 radiant damage.
14	Spatial Displacement. You can cast misty step once for every two contamination levels you have gained. You regain these uses when you finish a long rest.
15	Tentacled Limb. One of your arms becomes a fleshy tentacle. When you make a melee attack on your turn, increase your reach by 5 feet.
16	Spider Climb. You gain a climb speed equal to your walking speed. You can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
17	Whispering Voices. You gain telepathy to a range of 10 feet, but other people hear it as their own voice. If you have 10 or more contamination levels, the range extends to 60 feet.
18	Belly Maw. A toothy mouth appears on your stomach, which you can use to make unarmed strikes. If you hit with it, you deal piercing damage equal to 1d6 + your Strength modifier.
19	Eyeless Sight. Your eyes become milky orbs, and you gain blindsight to a range of 10 feet. If you have 10 or more contamination levels, your eyes rot out, and dim octarine light burns in the sockets. Your blindsight increases to 30 feet, but you are blind beyond this radius.
20	Arcane Blood. Gain an additional spell slot of the highest level you can cast (to a maximum of 5th level). If you don’t have spell slots, your hit point maximum increases by an amount equal to your level. Double with 10 or more contamination levels.

Eldritch Madness

Characters exposed to eldritch horrors must not only worry about the physical contamination but must also worry about the mental stress of eldritch madness on their minds. For many, it is often the mind that is the first to break due to the lack of outward signs that present themselves until it is far too late. For player characters, the madness is measured in multiple levels and characters gain levels of madness, as specified in the effect’s description.
A character exposed to any source of eldritch madness, even if no save DC was required from the source, will have to make a madness save that day when they take a long rest if they did not already gain any eldritch madness that day. This madness save is a Charisma save with a DC equal to their eldritch madness level. On a fail, they gain a madness level. Upon reaching the maximum eldritch madness level or receiving a number of Eldritch Insanities higher than a creature's Intelligence modifier (minimum of 1), the creature has gone completely insane and their mind is shattered with them no longer being themselves.

(The eldritch madness presents in many dark cruel ways)

Madness Levels

A creature suffering the symptoms of eldritch madness suffers its current level as well as all lower levels.

Level	Symptoms	Level	Symptoms
1	None	11	Restless (Long Rest +1 Hour)
2	None	12	Paranoia *Advantage on Perception Skills Checks *Disadvantage on Charisma skills checks
3	None	13	Eldritch Gift *Choose 1st level Warlock Spell. Gain use once per day.
4	Vice addiction (Minor)	14	Mind Rage (Gain Barbarian Rage +1 Use)
5	Restless (Long Rest +1 Hour)	15	Delerium addiction
6	None	16	Eldritch Gift *Choose 2nd level Warlock Spell. Gain use once per day.
7	Compulsion (Minor)	17	Immune to Frightened & Charm conditions
8	None	18	Eldritch Gift *Choose 3rd level Warlock Spell. Gain use once per day.
9	None	19	Memory Loss
10	Eldritch Insights *Lore / Arcana skill checks +2	20	Complete Eldritch Insanity!

Eldritch Insanity

In addition to suffering symptoms, each time a character gains a madness level makes a Wisdom save at the DC of the current madness level with a failure resulting in an Insanity!
The Game Master may choose the Instanity, or determine it randomly by rolling on the Insanity Table. If the result is the same as insanity affecting the creature, the GM chooses a different one or rolls again. A character that gains more eldritch insanity than their Intelligence modifier is immediately a victim of total Eldritch Insanity and is mentally completely gone regardless of the current level of Madness levels they might possess.

Die Roll	Insanity
1	"I am incomplete, the mutation will make me whole. I must do everything to understand it even if some say it is unwise."
2	"I am the last pure body left... all have fallen to corrupted Eldritch Horrors and now they hide in the flesh of everyone else."
3	"The cure is in the organs of a select few, only I can find them, once I consume the parts of them I will be the cure!"
4	"I am the cure, drink my blood to be saved from the Eldritch Contamination. Watch as my blood makes it die!"
5	"My mind is in this dark future, but my body is in the past. I must warn everyone of the coming doom!"
6	"The darkness of my mind is the only safe place, talk to no one, and the touch of the contamination cannot hear or find me."
7	"Flesh must be given to the contamination, if I feed it someone else it will spare me as long as I continue to feed it."
8	"I serve the master of the contamination and am only like this to help my cover, I will take my secrets to Halarahh!"
9	"I must be the target of different kinds of magic as I can to prevent myself from becoming contaminated."
10	"I can hear the magic talk, I can hear it inside me and others who can wield it. It must be freed!"
11	“I wish I didn’t have all these useless organs inside me.”
12	“ The contamination is a blessing that will transform me into a wondrous creature.”
13	“The monsters are civilians trying to live a peaceful life! We need to protect them!”
14	“I must wear a flesh coat made from my slain enemies to gain their strength!”
15	“My companions died in the ruins. I’m sorry friends, you are merely ghosts haunting me, you aren’t real. Stop trying to talk to other people.”
16	“I need to eat everything I can find. It’s probably going to be my last meal.”
17	“Halarahh is so beautiful at night. I could spend forever wandering the streets by moonlight. We should go tonight! Let’s go every night!”
18	“Don’t you fools get it?! If you die in Halarahh, you die IN REAL LIFE!!!!”
19	“A sinister cabal of disembodied hands is plotting against me.”
20	“I must go into the ruins and kill. Rip and tear, until it is done.”