The Elder Brain (Homebrew)

Perhaps you were unlucky enough to find yourself alone in the Underdark. Perhaps you were stolen in the night and dragged about a nautiloid to become a thrall. Perhaps you sought out an Illithid colony intentionally. However it happened you caught the attention of an Elder Brain, and it decided to strike up a deal, granting you psionic power previously thought to only be found in the ruthless tentacled minds of Mind Flayers and their ilk. You use your connection to the Elder Brian to shape your mind and the minds of those around, bending their thoughts to your will and convincing their brains to replicate effects impossible to accomplish.

Expanded Spell List

The Elder Brain lets you choose from an expanded list of spells when you learn a warlock spell. The following spells are added to the warlock spell list for you.

Elder Brain Expanded Spells

Spell Level	Spells
1st	command, Tasha’s hideous laughter
2nd	blindness/deafness, phantasmal force
3rd	protection from energy, bestow curse
4th	confusion, phantasmal killer
5th	geas, modify memory

Dominant Mind

Starting at 1st level, your Illithic knowledge gives you the ability to touch the minds of other creatures, bending them to your will. Whenever you deal psychic damage to a creature with an intelligence score of 3 or higher you can use your bonus action to force that creature to make an Intelligence saving throw against your spell save DC. On a failure the creature takes 1d4 extra psychic damage and they are vulnerable to psychic damage until the end of your next turn. On a success, they take half of 1d4 psychic damage. You can use this feature a number of times equal to your Charisma modifier {{modifier:cha}} (a minimum of once).

You regain all uses of this feature after a long rest. The damage increases to 1d6 at 6th level, 1d8 at 10th level, and 1d10 at 14th level.

Intelligent Feast

At 6th level, you learn to magically ward yourself against attack and to turn an enemy’s failed strike into good luck for yourself. As an action, you can cause a creature that you can see within 120ft of you to make an Intelligence saving throw against your Spell Save DC. On a failure, you drain a portion of the creature's mind and use it to replenish yourself, the creature takes 2d10 psychic damage plus your charisma modifier, healing you for the amount shown on the dice and the creature is stunned for a minute or until it succeeds on an Intelligence saving throw. A stunned creature can attempt to end its stunned condition at the start of each of its turns. On a successful save, the target takes half damage and no other effects are applied. No effect if the creature has an intelligence of 3 or lower.

You can use this feature once per short rest.

Sharpened Thoughts

Starting at 10th level, your thoughts can’t be read by telepathy or other means unless you allow it without first succeeding on a Charisma saving throw (DC {{savedc:cha}}). If a creature fails the save, you are instantly aware that it tried to read your thoughts and the target takes psychic damage, ignoring resistance, equal to your Warlock level {{classlevel/1}}. On a successful save,  the creature can read your mind without your knowledge (unless otherwise specified), but the creature takes psychic damage, ignoring resistance, equal to half your warlock level {{classlevel/2)@rounddown}}.

You also gain resistance to psychic damage.

Illithid Summons

At 14th level, you gain the ability to summon up to 3 Intellect Devourer to help you in battle, and feast on your enemies' minds to feed your shared Elder Brain. You can communicate telepathically with one of the Intellect Devourers as long as the two of you are on the same plane of existence. In combat, an Intellect Devourer rolls its own initiative but you can give it commands as a bonus action, if there are more than one, the command will be obeyed by all. If no commands are given it will instinctually attack any creature that dealt damage to you last using its claws for both attacks. 

An Intellect Devourer disappears if you are incapacitated, its HP is reduced to 0, or at a duration of 1 minute. You can summon up to 3 Intellect Devourers per long rest.