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Friday, October 9, 2020

Dungeons & Dragons - A Guide to the Brain in a Jar

Today we're going to look at a really fun D&D monster: The Brain in a Jar. I'm going to go through each edition and pull out the lore so we can get ideas on how to use this really weird, really cool monster.

My favorite NPC in Icewind Dale: Rime of the Frostmaiden is Veneranda - a brain in a jar connected to an animated suit of armor. I've always like the brain in a jar, a really weird, somewhat hilarious D&D monster. The idea of making a guide to them seems like a lot of fun, so let's do it!

Yes, there is a D&D mini for the brain in a jar. It is tiny! I used to always worry about losing it, but I never did. 

Reaper has a brain in a jar mini, too.

AD&D 2nd Edition - Ravenloft Monstrous Compendium Appendices I & II

I think this is the first appearance of a brain in a jar. It's called The Living Brain, a unique NPC/villain from the Demiplane of Ravenloft. The brain's story goes like this:

Rich Kid: Rudolph Von Aubrecker was a spoiled son of the ruler of Lamordia. He was injured badly at sea and washed up on shore.

He was brought to Victor Mordenheim (a major NPC in 2e Ravenloft, basically Dr. Frankenstein), who saw that he was going to die.

Save The Brain: Victor extracted the brain and kept it alive. After a year, he saw that it actually started to grow. He tried to destroy it, but found he couldn't - the brain used psychic powers to stop him. It then forced Victo to build it a magical support system.

The Brain Flees: The brain took control of Mordenheim's assistant, and they fled to the Sea of Sorrows.

Mind Control: The brain can control many creatures at the same time. It is trying to take control of Dementlieu, a domain of dread tun by Marcel Guignol.

Traits: It does not need food except for the nutrients in its fluid bath. The brain does sleep: "..only in dreams can it experience the physical sensations to remain sane."

Escaping the Brain: When the fluid is replenished, the brain is helpless and comatose for one hour. During this time, some victims under its control might be able to break free.

D&D 3rd Edition - Libris Mortis

This 3rd edition sourcebook gives us the brain in a jar as we know it. Traits:
  • It is an undead creature.
  • It possesses potent magical powers.
  • It can fly!
  • Has blindsight.
  • Weighs 25 pounds (this includes the weight of the container).
  • Can telepathically speak to creatures within 100 feet.
The Ritual of Extraction: How do you make a brain in a jar? "The ritual of extraction, the spells of formulation, and the alchemical recipes of preservation are closely guarded secrets held by only a few master necromancers."

The creation process is fraught with danger, because the brain gains the power to control the minds of others.

Abilities: The brain has powers:
  • Mind Thrust: I guess this targets a creature it can "see." CHA save or take 2d10 damage.
  • Madness: If you target a brain in a jar with a mind-affecting/probing power, you start to go mad due to "direct contact with its tortured mind."
  • Psionics: Suggestion, telekinesis, and dominate person.
  • Rebuke Undead: It can command undead like a cleric. 

The Warlord's Subterfuge: Further on in this book is a short adventure scenario called "The Warlord's Subterfuge." There is a nasty encounter here where a brain in a jar is hidden in the base of a throne - it can see out through a little slit. The group is attacked by an armored hulking corpse while the brain uses its powers in secret. 

The heroes may think they killed the warlord (the hulking corpse), completely unaware that the warlord is right there in the throne - the brain in the jar.

The Twilight Tomb

In this adventure, which I've never even heard of prior to writing this article, is about this:

"A 'loose' piece of the star elf demiplane of Sildëyuir contains a single glass citadel that serves as the tomb of a corrupt star elf called Mourel Duskwalker."

A star elf? What the heck is that? How did I miss this? It's so weird to me that despite spending many years reading up on D&D lore, there are entire sections of D&D history that I am completely unfamiliar with.

The basic idea of this adventure is that the heroes will enter a glass citadel and will be trapped inside until they can open a portal back to Faerun.

The Night Realm: This is a "splinter demiplane." Two days in the normal world equal one day here. Sonic spells do more damage in the Night Realm.

The Bad Guy: The villain of this adventure is a star elf brain in a jar. Deep in this crystal tower (room 49) is the vault of Mourel Duskwalker. He is now an "evolved brain in a jar." His apprentice Kyjal recovered his head after his execution.

Brain in a Girallon: Whoa... get a load of this. He created a zombie Girallon (that's a giant white ape with four arms), carved a cavity in its chest, and placed the brain in the jar in there! What!?

The girallon can cross its arms over the brain to provide it with cover. If the zombie is destroyed, Mourel flies out of the cavity and takes cover in the room's dome. 

Imbrudar, the Brain in a Jar

In this online article, D&D designer Robert Wiese decided to "give an inoffensive creature a facelift" and here were are. This article is definitely an example of a bygone era of D&D, where someone uses powers and abilities from newer books to create a surprising/effective/"gamebreaking" result.

3e, I think, was and is a dream system for people who like to tinker.

Imbrudar's Origin: Imbrudar was created in a lab and dominated its creator, forcing them to move it to a fortress. It began a quest to unlock the powers of its own mind, seeking to control every creature that came near it.

The author stats out a few versions of Imbrudar.

Imbrudar as a Budding Psion: This is a beefed-up version of the normal brain in the jar.

Imbrudar, Finally Self-Mobile: It uses a psionic power called metamorphosis, which allows it to change shape. "You acquire the physical qualities of the new form while retaining your own mind."

"When the change occurs, your equipment either remains worn or held by the new form (if it is capable of wearing or holding the item in question) or melds into the new form and becomes nonfunctional."

The duration is 1 minute per level, so.. wow.

Imbrudar, Master Psion: It can permanently switch minds with another creature! It could move from body to body if it wanted to.

It likes to use a power called decerebrate, which is simple and effective: "With decerebrate, you selectively remove a portion of the subject’s brain stem. The creature loses all cerebral function, vision, hearing, and other sensory abilities, and all voluntary motor activity. The subject becomes limp and unresponsive."

D&D 4th Edition - Open Grave

I love this book so much. We don't just get a 4e brain in a jar, we also get VARIANTS!

Traits: The brain has similar powers to the 3e version. It does have telekinetic thrust, which is a minor action (which is an additional sub-attack on its turn) that can push you up to 20 feet and, if you hit a wall, you fall prone.

"Anything that disturbs this brain's private meditations antagonizes the creature."

Brain Fluid: The preservation fluid in a brain's jar is valuable - it can be distilled into an elixir that imparts the memory and knowledge of the jar's occupant brain.

Putting a Brain to Rest: A brain can be returned to a host body to grant it a peaceful death

Brain in a Broken Jar: These are created though incomplete rituals, spoiling fluids, or damaged containers. "A brain in a broken jar is usually deranged."

It has "faulty invisibility," meaning that it becomes invisible for 1 round. This power recharges on a 4-6.

Brain in an Armored Jar: Some of them exist to chronicle past history and lore. This has "psychic overload," a power that does psychic damage and drains a "healing surge" (which is sort of like a hit die in 5e terms). It can also emit an electrical discharge, which can hit all within 15 feet with lightning damage that dazes.

Exalted Brain in a Jar: A brain taken from a powerful creature by devotees to preserve the subject's knowledge and wisdom. When a creature hits it with a melee attack, it can teleport them up to 40 feet away. Fearful Recoil: It can force an enemy back 20 feet.

Stardock Under Siege

This adventure is meant to be run at conventions and game stores where a bunch of tables full of D&D players work together to overcome the obstacles in the adventure.

Stardock: Stardock is a floating island in space, orbiting Toril (the planet that is the Forgotten Realms). You can travel to Stardock through Undermountain (the dungeon under the city of Waterdeep).

Stardock is now run by a githyanki named Urlon, who is a member of the Sha'sal Khou - a group that wants to make peace between the githyanki and the githzerai.

In this scenario, a horde of mind flayers are invading Stardock.

Bone Pod: One or more groups will end up exploring a "bone pod," which is a mind flayer vessel. "The bone pod houses an alhoon, some brains in a jar, and a platoon of dead illithids awaiting reanimation and deployment." An alhoon is a mind flayer lich.

In case you are wondering, there is a rune circle/"necrotic power cell" in the floor that siphons energy from living creatures to reanimate the dead illithids (who use bodak stat blocks).

The brains in a jar seem to be sidekicks to the alhoon. Their job in this encounter is to try to move the characters onto the necrotic circle.

This adventure looks really insane. Apparently some people who played through it thought that it was too easy.

Lost Laboratory of Kwalish

This adventure involves the heroes heading to the laboratory of the legendary Kwalish (of "Apparatus of Kwalish" fame) - the remains of a planar craft. Kwalish left, and it is now home to a bone devil.

(pg 16) M8 Control Room: The planar craft is now a part of a sort of demented magic/technology infused monastery, which is watched over by 5 "enlightened ones" who are actually brains in jars. Each has been chained to the other to form a hive-mind consciousness.

The brains were once companions of Kwalish. They were killed by a sphynx. Kwalish turned them into brains in jars, and planned to make them new bodies, but was driven away before he could complete the task.

Their names were Alton, Broderick, Corliss, Dunstan and Editha.

The brains are attached to a power grid, and need energy cells found in area M10. for them to be moved elsewhere. 

M10. Treasury: This treasury contains another brain in a jar - the brain was originally a bone devil. It had been investigating the building when its brain was magically drawn into a jar.

That's a heck of a trap, right? Make a save or your brain is pulled into a jar?

New Body: This brain wants a new body. It can use the equipment in the laboratory to return to its original body., it just needs the heroes to bring them one - preferably the body of the Grandmaster of the Monastery.

Kwalish's Notes: This lab contains notes written by Kwalish, instructions for making artificial bodies for the brains in jars.

Later in this module, it says that the brains can guide characters through the process of transferring their intellect into a host such as a slain monk from the monastery, or even a modron.

"This process requires a successful DC 14 Wisdom (Medicine) check or Dexterity check with thieves' tools or tinker's tools. However, on a failed check, the brain is destroyed.."

The idea of the party rogue having to roll a DEX check to extract a fellow party member's brain is hilariously intense to me.

Crafting a New Body: The adventure even gives us some rules on making a new artificial body.Arcana Check or DEX check with tools DC 16. Each body requires an energy cell.

Icewind Dale: Rime of the Frostmaiden

We have the 5e stat block for the brain on page 279.

  • Unwilling: "...the brain of a mortal being (willing or unwilling) is encased in a glass jar ..."
  • Immortal: The brain is rendered immortal and imbued with psionic powers.
  • Talks Too Much: "It enjoys conversation so much that it is prone to talking for hours on end...'
  • Insanity: The brain in a jar is likely to gain a form of insanity, including: dementia, schizophrenia, or paranoia. 
  • Hefty: It now weighs 125 pounds, as opposed to the 25 pounds in 3rd edition. 
  • Slow Flight: The brain flies only 10 feet per round, slower than in other editions. 
  • Life Detection: It can detect sentient creatures within 100 feet.

It can cast a pile of spells, including:

  • Mage Hand
  • Zone of Truth
  • Charm Person
  • Hold Monster
  • Tasha's Hideous Laughter

Chill Touch: It has chill touch as a ranged attack,doing necrotic damage and preventing healing.

Mind Blast: It also has mind blast! 50 foot cone, doing psychic damage and stunning those who fail the save.

Veneranda: In room Y19E. Liquefaction Chamber on pg 248

"Behind the tables stands an ornate suit of armor. Where the head should be is a swollen human brain floating inside a canister of translucent fluid."

Veneranda was a neutral evil wizard who extracted her own brain and became a brain in a jar. The jar is affixed to a helmed horror.

Her goal is to restore the city of Ythryn to its former glory. 

Ritual of Brain Transfer: This room is a ritual room designed to transform a living creature into a brain in a jar. 

"Veneranda can use the equipment in this chamber to transform one humanoid into a brain in a jar. This ritual takes 24 hours and results in the death and liquefaction of the subject's body. Veneranda doesn't allow anyone to view the ritual while it is being performed."  


Cracked thinks the Brain in the Jar is one of the most idiotic monsters of all time.


Yildo said...

A wonderful brain-in-a-jar character in popular culture is Brain Drain, a supporting cast member in the Unbeatable Squirrel Girl comics.

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