Juiblex

Juiblex
Alignment	Chaotic Evil
Divine Rank	Demon Lord
Domains	Chaos, Corruption, Evil, Ooze
Home Plane	Slime Pits (222nd layer of the Abyss)

Juiblex, (pronounced Joo-ee-blex) also known as the Faceless Lord, is the Demon Prince of Slime, Ooze and Filth. Among the lessers of his kind, Juiblex is a monstrous mass of mobile ooze in a sickly rainbow of dark, putrid colors dotted with an ever-shifting array of jelly-like burning red eyes. Near-mindless, Juiblex seeks only to consume and defile, with vague ambitions of swelling in power until all of reality has dissolved into a slick morass of sludge, with nothing but ooze remaining. "Worshipped", if such a term can be used, by the vast array of slimes, Juiblex has little appeal to most humanoids, although he does occasionally develop worshippers amongst the crazier denizens of the Underdark. As a consequence, his fellow Demon Princes mostly ignore him, not considering him worth the effort to destroy.

Juiblex shares the 222nd layer of the Abyss, Shedaklah, with the Demon Queen of Fungi, Zuggtmoy, with the two constantly battling for total dominance of the layer. In 1st edition, he actually had his own layer; the 528th.

Juiblex received a surprising buff in 4th edition; covered in a Demonomicon of Iggwilv entry in Dungeon Magazine #188, the 4e Juiblex is literally the sapient manifestation of the infectious nature of evil. Basically, in 4e lore, the Abyss was created when Tharizdun came into contact with the Seed of Evil, the crystalized remnants of a dead universe consumed by the Obyriths, and plunged it into the Elemental Chaos. This metaphysically wounded the entire plane, creating a gaping, infected abscess in the metaphysics that is the Abyss. Juiblex is the infection manifest; when the Seed first broke into the Elemental Chaos' "flesh", the resultant surge of corrupted blood and pus and rotting meat became self-aware. And that living mass of liquid putrefaction was Juiblex. As such, Juiblex is the oldest Demon Prince in the entirety of the 4e cosmology; he witnessed the escape of the Obyriths and their battle with Tharizdun, which means he alone knows the true purpose of the Abyss: to consume all reality and wipe it away into nothing.

Thrall of Juiblex

Servants of Ghaunadaur/Juiblex gains another slime-based prestige class, to represent worshipping him as a demon lord instead of a greater deity.

Like the Slime Lord, this prestige class also culminates in changing your anatomy, but is less focused on drastic tentacle attacks and accumulating immunities and more on wreaking havoc with goo.

From the get go, they secrete sickening slime from their skin, which can turn corrosive in later levels. They can also spread diseases and spit acid too. Not only that but they summon various demons and Ooze creatures as spell like abilities, so always handy if you need a mindless minion.

The prestige class also seems to be so awesome that they forgot to give it a poor save modifier, so it gets the best progression for Ref/Fort/Will saves as well as the best BAB progression.

Pathfinder

"Jubilex" (pronounced Joo-bee-lex) is apparently open-game licensed, as he has appeared in Pathfinder, where he has been promoted to have a slightly broader portfolio (poison and sloth) and is now one of the demonic patrons of the Drow, probably to encompass his dual role as Ghaunadaur in FR.