Homebrew Illithid Species Details

The illithids are among the most deadly of the aberrations. These hyper-intelligent beings feast on the brains of their captives, giving them their more commonly-used name, “mind flayers”. These beings are powerful, and as such, you should consult with your GM before playing one of these hideous monstrosities.

Hive Minds

Illithids congregate in large groups known as colonies. Here, they sacrifice most of their freedom to their elder brain in favor of safety. They still have personalities, but are, for the most part, just servants. There are two exceptions to this rule: ulitharids and renegade illithids. Ulitharids are the result of a mutation in the process of creating ilithids. They can overpower their elder brain if needed, and will almost always split off to create a new colony.

Renegades are a bit different. These illithids create tension in the colony because if one mind flayer leaves, more usually follow. Without an ulitharid, they can’t create a new colony, and will most likely either die off or end up serving a new master. A popular example of a renegade illithid is Nihiloor, from Waterdeep: Dragon Heist, who serves the Xanathar.

Illithid Conception

Illithids, once or twice in their lifetime, lay clutches of eggs. These eggs hatch into tadpoles, which are usually kept in the elder brain tank and fed brains to grow. When a humanoid is subdued and brought to the colony, the mind flayers might put them through the process of ceremorphosis. In this process, a tadpole is inserted into the ilithid-to-be, where it eats the host’s brain and takes its place. After this happens, it takes about a week for the host to transform into a mind flayer, and while it leaves a trace of the host’s old personality on the new illithids, they are generally entirely new creatures.

Not all humanoids are taken in as new mind flayers. Usually, their brains are devoured by other mind flayers, but sometimes they are taken through the process of becoming a thrall. In this event, the humanoid has their mind completely wiped and are trained for their new job as a thrall. Some colonies can retain their thralls’ personality, others can even implant their thralls with psionic powers.

Illithid Names

Illithids usually decide their own names at conception, when the parasite first enters the brain. However, it can take longer for them to decide their names. Their names are almost always spoken in Deep Speech, and are formed of any combination of syllables. Some mind flayers identify themselves by their elder brain’s name, as well, which is just another illithid name.

Illithid Names: Ankizuve, Graphal, Kedraresk, Lirdurul, Luoolleveru, Qhasask, Qibull, Rualt, Tassk, Vaulix

Illithid Traits

Your aberrant nature manifests in various psionic traits that all mind flayers share.

Languages

You can speak, read, and write Common and Deep Speech, and can read and write Qualith. Deep Speech is a language spoken by most aberrations, and Qualith is the written language of mind flayers that consists of patterns of four lines imbued with psionic energy. This form of writing conveys not only text but also the author’s thoughts.

Ability Score Increase

Your Intelligence score increases by 2, and either your Wisdom score or your Charisma score increases by 1.

Age

Ilithids consider themselves to be born the moment the tadpole enters their brain. They mature in about 2 weeks and usually live up to 126 years.

Alignment

Ilithids lean towards lawful, usually conglomerating themselves into colonies under a single ruler. Most ilithids are also evil, thinking most of their own personal gain and disregarding any detriment to those not in their colony.

Size

An Ilithid’s height and weight usually depends on the creature they were before being transformed. Your size is medium.

Speed

Your base walking speed is 30 feet.

Aberration

Your creature type is aberration, rather than humanoid.

Darkvision

You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can’t discern color in darkness, only shades of gray.

Magic Resistance

You have advantage on saving throws against spells and other magical effects.

Intrusive Mind

You can speak to anyone telepathically up to a range of 120 feet.

Tentacles

Your four tentacles act as a natural weapon, which you can use to make unarmed strikes. If you hit with it, you deal piercing damage equal to 1d4 + your Strength modifier, and you may attempt a grapple check to grapple the target you are attacking.

Extract Brain

If you have an incapacitated creature grappled with your tentacles, you may make a melee attack against them, using Intelligence for the attack roll instead of Strength. If it hits, they take psychic damage equal to 1d10 per level + your Intelligence modifier. If this reduces the target down to 0 hit points, you instantly kill them by extracting and devouring their brain. When you do so, you gain the memories of the creature, and you gain enough nourishment to sustain yourself for a week. You can use this ability once, and regain the ability to use it upon completing a long rest.

Innate Psionics

When you reach 3rd level, you can cast the detect thoughts spell and the levitate spell each once per long rest. When you reach 5th level, you can cast the [Tooltip Not Found] spell a number times equal to your Intelligence modifier (minimum of once) per short or long rest. When you use your psionic blast, you must wait 30 seconds before you can use it again. When you reach 9th level, you can cast the dominate person spell once per long rest. Your spellcasting ability is Intelligence for these spells.