Can illithids...
De-brain each other?
Prior to Lords of Madness, I would normally say "definitely." Estriss from the Spelljammer novels violently de-brained at least two other mind flayers during the series.
However, while Lords of Madness doesn't explicitly say "No, they can't," it does say that illithid mucus (the layer of slime all illithids have on their skin) IS resistant to tentacle acid. Who's right?
Ooh thats just what an evil race needs to make it all the more evil. A Sociopathic Illithid. Damn.
I tend to agree, if you are the gm and you have a cool idea, don't let some rule ruin it for you ... especially in Planescape where rules are just a difference in philosophy between you and the writer. ::smirks::
Y'know, I've also wondered about decerebration, of, say, exemplars. Since there are numerous referances to the Illithid Empire at its height overshadowing the blood war, I'm inclined to think that the mind flayers can eat outsiders' brains. I also assume a summoned outsider's body dissolves away upon death.
"What're we having tonight?"
"Tanar'ri?"
"Ugh, too spicy."
"Archon, maybe?"
"Kind of light ..."
"How about Slaad?"
"Well, you never know with them ..."
"Humph, if you don't want to eat out, just say so."
Would the brain of a petitioner, as opposed to a living humanoid, provide meaningful sustenance to an illithid? There's a tough one. 
"Meh, kind of bland ... "
Giths? 
*salivates*
*salivates*
Yeah, thought so!
:help!!:
:eatYou:
By the above logic, the only things restricting whose brains a mind flayer can eat are,
1- Size: An illithid might be able, with some effort, to eat a giant's brain, and a group might concievably stand around and dine on a restrained aboleth, but in the normal scheme of things, if a being is larger than large size, the 'thid's going to have a tough time of it.
2 - Elemental composition: Is eating the brain of an efreet considered an extreme sport?
3 - Undead: Ewww. Rotting brains? What am I, salmonella?
By the above logic, the only things restricting whose brains a mind flayer can eat are,
1- Size: An illithid might be able, with some effort, to eat a giant's brain, and a group might concievably stand around and dine on a restrained aboleth, but in the normal scheme of things, if a being is larger than large size, the 'thid's going to have a tough time of it.
2 - Elemental composition: Is eating the brain of an efreet considered an extreme sport?
3 - Undead: Ewww. Rotting brains? What am I, salmonella?
Is debraining an exemplar actually fatal, though? Many exemplars can withstand ridiculous injuries, and have regeneration, and aren't 'normal' anyway...
I just had a very weird idea.
The Astral Plane has a lot of 'astral winds' -- mental emanations that come from the thoughts and feelings of people on other planes. If there's a massive battle on the Prime, for example, a whole bunch of strong astral winds are formed somewhere on the plane.
Illithids eat brains for one reason. They can get almost everything else they need from other organs of the body, except a brain's psychic awareness.
Can an illithid eat astral emanations, which, after all, are made from pure thought? Would it derive any sustenance from it, or just pleasure? Is it like sugar to them?
--Things with immunity or resistance to acid would probably pose a problem. (Would a ring of acid resistance protect against debraining)
--Outsider DR is damage that heals instantly, this may well stop extracting a brian with tentacles, since the skull heals or is just too thick. Same deal with regeneration, probably.
--Exempelar brains are probably pretty wierd, considering they're quite diferent from mortal brains--being composed of the stuff of the exempelar's plane and all. It might have side effects, or maybe a mind flayer who ate too many archon brains would become LG.
I think you're giving Azure ideas. I don't want to see a sugar high ghaik. EVER. They'd need actual nutrients in adition to the psychic stuff, so I guess they could becone "hind flayers" like in that haiku, and get thier psychic energy from the astral.
But then you have the scariness factor to consider. It's kinda hard to take a hind flayer or spleen flayer seriously.
Brains, they're grrrrrrreat!
--Things with immunity or resistance to acid would probably pose a problem. (Would a ring of acid resistance protect against debraining)
I think acid immune creatures should be immune to brain extraction. As for resistant... the MM entry really ought to provide "does X amount of acid damage per round," to determine what happens in the case of acid resistances.
Mostly agree on the DR. I think there are a few psionic abilities (under Psi-Warrior, I think) that can technically be used to give effective "pluses" to a tentacle, but the average illithid won't have those.
You are what you eat...
Sugar high illlithid = an illithid who has just consumed the brain of a psion with a fairly full power point reserve. :shock:
I don't know. I don't want to mess with something calling itself a 'spleen flayer.'
Think about the practical complications though, a torso is harder to grab than a head, and you'd need larger and stronger tentacles and more time.
I think Spleen Flayer would be, like, an AMAZING April Fool's entry. =D
You know, I think that average ilithid ilithid is pretty content with the brains of lesser "catlle" races (demihumans, humanoids, monstrous humanoids and gigants). Eating brains of greater planar races would be just plain stupid even for ilithid (yes, you can eat their brains but they will reform on their home plane and then will probbably go after you).
Then again, there is always "Hanibal Lector" ilithid who would consider finding way how to eat these "impossible" brains mental chalenge.
Secondly there are always adventurers, and you know how many wizards ask them to bring the head of this creature or that crature. (Ilithids in disguise). 
And fianly have you asked yourselfs why Mi-Go collect brains anyways. They are probbably working as food suply for Mc Ilithids space restourants.
Fairy brains - shugar and drugs. Bad combo.
That's why they want a plane spanning empire. It's pointless to kill a summoned creature. You have to eat an outsider on it's home plane to kill it permanantly, right?. Unless it is a mortal outsider like a tiefling (mmm ... spicy). I always figured petitioners actually accend pretty quickly, because the most of the outer planes seem way underpopulated compared to the primes, with certain exceptions like the Abyss. 'Native outsiders' or whatever, y'know planar humanoids, are probably exotic and expensive fare.
Goblins are fried chicken, or chicken wings.
Gith are a thick juicy steak (or a portabella burger for you vegie-lovers out there)
http://www.giantitp.com/comics/oots0031.html
Gith are a thick juicy steak (or a portabella burger for you vegie-lovers out there)
Githyanki psions.
I think Homer Simpson said it best - "Ohhhhhh"
Absolutely drenched in psionically charged cerebrospinal fluid! And that pineal gland!!
Well, if says that they cannot becouse of that muckus that protects their brains, than officialy they cannot.
But consider this: how many people have actualy read "Lords of Madness" or spelljamer books. I mean every society have its debased and sick persons who comits atrocites like canibalisam.
I guess that such ilithid would not even need his tentacles. You alredy know that ilithids have invented various tools that they attach on their tenticales (like drills for example), and muckus can always be washed or peelled away.
I guess that some minor bit of cannon and rules should not stop you from creating interesting villian: ilithid version of Hanibal Lector. :twisted:
One-eyed, one-horned, flying, purple people eater says: "Monsters are nature's way for keeping XPs fresh."