EPT
Madness Domain
It is the faint whisper, constant and inscrutable, yet doubtlessly malicious. It is the infinite fog in which countless shadows tremble, just far away enough that you cannot be quite sure they are there. It is the relentless pulse of liquid dripping from the canopy of an unfathomable cave or the maw of a ravenous horror. It is the eyes, bloodshot and quivering, staring into the abyss, and knowing that it stares back, not with two eyes, but with thousands.
Most flee from this sinister call, screaming and frothing, unable to dislodge the cursed memory from their addled minds until death frees them from their torment. Yet there are those who embrace the eldritch touch with a sickening grin, who allow the whispers purchase, who exalt Madness in all its nefarious forms. In return for their sacrifice, the gods of insanity bestow the authority to enforce their dark wills, to spread their gospel of unravelling to all those to whom it has not yet beckoned.
Clerics of Madness worship at the Altar of the Abyss, choosing for their god one of the unnameable horrors which lurks within. These bearers of eldritch evil unleash their gibbering tongues upon the realm of mortals, poisoning the innocent and the just with their vile scriptures. As more souls writhe and wail under the twisting tones of discord and chaos, the gods of madness grow greater and greater. In the realm of Iris, the Mad pantheon includes Krosesophin Undone, The Lady of the Silent Song, Elophreshuk the Thousand-Fold, and One Among Many Among None.
Madness Domain Spells
- 1) Dissonant Whispers, Arms of Hadar
- 3) Crown of Madness, Phantasmal Force
- 5) Hunger of Hadar, Fear
- 7) Confusion, Evard’s Black Tentacles
- 9) Dominate Person, Seeming
1) Eldritch Awakening — You may let your madness flow through you to unsettle your enemies. During your turn, you may choose to froth and cackle wildly as a free action. Your skin-crawling distraction grants you ADV on your next attack roll. You may use this ability a number of times equal to your Wisdom modifier until your next Long Rest.
2) Channel Divinity: Encroaching Horror — You unleash the foul whispers from beyond the Abyss when your weapons strike true. When you expend a use of Channel Divinity for this feature, any attack roll you make that successfully hits forces your target to make a WIS save against your Spell Save DC. On a failure, your target is Feared. While Feared in this way, creatures utilize all of their actions to run from you so long as there is a safe way to do so. Furthermore, the target will not willingly come within 15 ft. of you. While it is Feared, the creature will suffer 1d6 Psychic damage at the start of each of its turns as the whispers try to claw their ways out. The Feared creature can repeat the WIS save at the end of each of its turns. Once a creature has saved against this attack, that creature cannot be subject to this Fear effect from you for the next 24 hours.
6) Vile Transformation — As their gods tunnel deeper into the recesses of their minds, Madness Clerics employ dark rituals to mimic their foul deities, aping the gods' profane perfection by desecrating their mortal flesh. You acquire a mutation that many will find disturbing and hateful. A Vile Transformation can be hidden for 24 hours by liberally applying a vial of holy water. Hiding your Transformation causes you to lose the benefits it provides. Otherwise, a Cleric with a Vile Transformation has DADV on Deception, Performance, and Persuasion checks. Choose your mutation from the following list:
- Stygian Rattle: Your tongue transmutes into a foul worm that speaks in a voice much like your own once did. You are Proficient in Intimidation and you double your Proficiency Bonus to Intimidation checks. You also receive a ranged spell attack (60 ft.) that deals 1d6+WIS Psychic damage on hit (use Cleric spellcasting modifiers).
- Willful Tentacle: One of your arms (choose which) stretches into a slimy tentacle that seems to act of its own will, a will that tends toward violence. You gain a melee attack (5 ft., single target) with a natural weapon (tentacle) that uses STR for the attack roll and damage roll. On a hit, this attack deals 1d6 Bludgeoning damage and Grapples the target.
- Fungal Oculus: One of your eyes buds into a horrific mass of eye-topped stalks, some of which obey your commands, others of which see things none are meant to see. You are Proficient in sight-based Perception checks and you double your Proficiency Bonus to such checks. You gain Darkvision of 60 ft. As a Bonus Action, you may use this trait to give yourself ADV on a ranged attack. You may gain ADV in this way a number of times equal to your WIS modifier per Long Rest.
- Insectoid Limbs: Your legs bifurcate into spindly bug-like limbs that dance with eldritch excitement, constantly itching to run toward screaming and blood. Your Speed increases by 10 ft. and you can perform a long jump or high jump without a running start. If you move 20 ft. or more before your Attack action, gain +2 to your attack and damage rolls.
- Voracious Maw: Your gut splits into a drooling maw, filled with concentric rows of hideous teeth. It perpetually hungers for the flesh of the untainted. You gain a Bite attack (Melee weapon attack, 1d10 Piercing damage) with which you have Proficiency. This attack can be used as a Bonus Action a number of times equal to your WIS modifier per Long Rest.
- Foul Feelers: Your fingers bend and flex without regard for the bones within, and, when they grasp for prey, they extend far from their former master. You gain a Claw attack (Melee weapon attack with a 15 ft. reach, 1d8 P) with which you are Proficient. This attack may be used as if it were an off-hand weapon.
8) Fell Smite — When you hit with a weapon attack, you deal an additional 1d8 Psychic damage. This damage increases to 2d8 at level 14.
17) Gospel of the Unspeakable God — Your demented whispers now beckon others into your god’s eldritch embrace. When a creature is under the effect of your Encroaching Horror, you may Charm it by making a successful attack against the same creature. While Charmed in this way, the creature will attack the nearest visible creature other than yourself as its senses are consumed by unearthly visions. If no creatures meet these conditions, it attacks itself instead. A number of creatures equal to your WIS modifier can be Charmed in this way at once.
If you want to read these thoughts on D&D, as well as any of my other random musings, you can do so at the N3rd Dimension.
That being said, this Domain is a lot like the Death Domain in that it's mostly intended for baddies (though I don't think Death is as inherently evil as Madness is, but that's an alignment tangent I won't venture down). 
