Base Class: Warlock
Hearing the mad whispers from a young age, mental stability has never been your strong suit. Without ever experiencing a moment of silence or a restfull night's sleep, your mind has always been teetering at the razor's edge of sanity. In return, the whispers have granted you power. When the lines between reality and a vision from the Abyss often blur, you have developed a keen eye in descerning between the two, making it hard for anyone to fool you with illusions.
While the price is high, the whispers have told of boundless arcane knowledge. Where the patrons of other warlocks see limitations, yours speaks of opportunity and secrets even the oldest of libraries can only dream of. What's the real harm of letting the voices slowly creep deeper and deeper, when such power is the reward?
Instead of an additional spell list, the Eldritch Abyss Warlock gains access to the full Wizard Spell list at the constant risk of insanity. Additionally, you can instinctively Speak, Read and Write Abyssal.
Used to Trickery
Gain advantage on all Skill checks to see through non-corporeal Illusion Spells up to the highest Spell Slot available to you.
Broken Mind
Starting at 1st level, every time you cast a Spell of the 1st level or higher, your Patron attempts to infulence your mind. You lose 1d4 Sanity Points per Level of the cast Spell. Once your Sanity points are fully depleted, you roll on the Insanity table.
| d100 Roll | Insanity |
|---|---|
| 1-5 | for 1d4 hours, Your Vision becomes Blurry and you can't descern individuals from oneanother |
| 6-10 | until your next Long Rest,Your Eldritch Blast fires one additional Projectile |
| 11-15 | Until your next Long Rest, you speak only Abyssal, but are unaware of it. |
| 16-20 | Until your next Long Rest, your Eyes turn black and ooze black ichor. Roll a d4, depending on the roll your sight changes: 1: you gain Darkvision up to 60ft, 2: you turn blind, 3: you gain disadvantage on Perception Checks based on Sight, 4: You gain Truesight up to 120ft |
| 21-25 | You are compelled to utter Eldritch invocations. Any Creature that can see you must succeed a WIS Save against your Spell DC. If they fail, they see you as an Eldritch Abomination and are frightened of you for 10min |
| 26-30 | Regain your last 2 used Spell Slots |
| 31-35 | Roll a d4. Depending on the outcome, one of your extremities transfigures into a tangled Mass of black Tentacles for 1 hour: 1: Right Arm, 2: Left Arm, 3: Right Leg, 4: Left Leg |
| 36-40 | Until your next Long Rest, you have Disadvantage against all WIS Saves |
| 41-45 | Until your next Long Rest, you gain resistance to psychic damage |
| 46-50 | Until your next Long Rest, you gain vulnerability against psychic Damage |
| 54-55 | Until your next Long Rest, you find it easier to influence others and gain expertise in Persuasion |
| 56-60 | Until your next Long Rest, all Abominations and Abberitions percieve you as one of theirs and become docile towards you. When attacked or offended however, they will still defend themselves |
| 61-65 | You summon 6d4 tiny Eldritch Abominations for 10min. They are the Size of Mice, consist of tendrils, eyes and teeth and swarm your body. You gain +2AC for the duration |
| 66-70 | All your Spell Slots deplete |
| 71-75 | Any Creature that sees you must Succeed a Wisdom Save against your Spell DC. If the fail, they percieve you as an enemy |
| 76-80 | You must Succeed a WIS Save against your own Spell DC. If you Fail, you become an NPC under the DM's Control and attack any Creature in Sight. This lasts until you are unconscious or until Greater Restoration is cast on you |
| 81-85 | For 10 minutes, you are shifted into the Abyssal Plane |
| 86-90 | You regain double the amount of Sanity Points you normally would |
| 91-95 | Until your next Long Rest, you reflexively read the surface thoughts of every creature within 30ft of you |
| 96-99 | You loose all inhibition and share a well kept secret with the next person you see |
| 100 | Madness Consumes You |
Sanity Points
As your power grows, you learn how to hold the Whispers at bay. You gain 20 Sanity Points per Warlock Level.
Eldritch Ward
At 6th level, you learn how to use the visage of your Patron to your Defence. Twice per Short Rest, you can use your reaction to impose disadvantage on your Enemy by flooding their mind with short glimpses into the Abyss. If they fail a WIS Save against your Spell DC, you also gain Advantage on your next attack until the end of your next Turn.
Fractured Thoughts
Starting at 10th level, your thoughts can’t be read by telepathy or other means unless you allow it, nor can you be scried upon. You also have resistance to psychic damage, and whenever a creature deals psychic damage to you, that creature takes the same amount of damage that you do.
Surrender to the Abyss
At 14th level, you gain the ability to relinquish Control and let the Abyss flow through you for 1 minute. As an Action you cause a veil of magical Darkness surrounds you in a 20ft sphere that you can see through. Creatures further away than 40tf can't target you and creatures within 40ft gain disadvantage on all attack rolls made against you. Once per round you fire an Eldritch Blast as a free Action, enhanced by 2 Eldritch Invocations of your Choice. You loose 20 Sanity per Round.
-
View User Profile
-
Send Message
Posted Mar 11, 2026well, this build is over 2 months old and has gone through a few iterations since. I just haven't found a way to un-publish this one. As it stands now, anytime a roll on the insanity table is triggered, Sanity fully resets to max. There are also other ways for him to either spend more for increased effects or recouperate some.
And yes, this is very punishing. But it's at the request of the player. The setting for his Character is that he used a Legend Lore Scroll on an artifact he really shouldn't have and drew the attention of an old, eldritch god, drowning his every thought in whispers and promises if he just gives into it. He wants that looming threat of insanity to be constant. Dunno why, didn't argue with it because from an RP standpoint i love the concept.
The Campaign is also fairly RP heavy so that does play into it. I'd never make a subclass like this for a meatgrinder or dungeon crawler campaign.
-
View User Profile
-
Send Message
Posted Mar 11, 2026This subclass just flat out sucks as written, I'm not going to sugarcoat it. Not only does it discourage using leveled spells at all, the sanity points don't reset. That's 20-400 sanity points in total, period, and unless you're leveling up like crazy, odds are you'll be insane forever just for...playing a Warlock outside of the usual Eldritch Blast spam. The 14th level feature flat out takes 200 out of the 280 sanity points you could feasibly have if you never once casted a leveled spell from level 1 to level 14 (which i HIGHLY doubt anyone would), and it lasts for a minute with no way to end it early. Meaning, again, TWO HUNDRED POINTS GONE. IN A SINGLE USE. And, using it literally one more time is GUARANTEED to cause insanity because of that problem, no matter WHAT level Warlock you are. If the goal was to have wizard cantrips, you could accomplish that with no punishment or risk just from doing 1 level of sorcerer as those two classes share a LOT of spells. And also get MORE of them. There's literally no point in taking this subclass outside of being a bully to your own character, and at that point why are you playing that character?
-
View User Profile
-
Send Message
Posted Dec 30, 2025I made this with the Great Old One Subclass as a base for one of my players at their request for our next Campaign. I'm aware there's significant risk built into the subclass, that was also at his request. The 100 roll is intentionally left rather vague to give the DM freedom to enact the consequences.
I'm happy to get any feedback and ideas to further improve this.