Here is a differen version of a pic [link] I planned to do for a long long time. I dedicate it to my friends Alessio and Marco.

I really worked hard to make it as it was supposed to be. It is the climax of the battle against Demogorgon in his fortress of Abysm, to recover the charm he is wearing in the pic. An ancient and powerful Vasharan symbol.

References:
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[link]

This is what I found on the net about him:
Demogorgon is the most powerful of al the tanar'ri demon lords. He is known as the Prince of Demons, a self-proclaimed title he holds by virtue of his power and influence; which in turn, is a title acknowledged by both mortals and his fellow demons.

Demogorgon appears as an eighteen-foot tall, reptilian (or amphibious) hermaphroditic tanar'ri with a somewhat humanoid form. Two baboon heads sprout from his twin snake-like necks, and his arms end in long tentacles. Demogorgon's two heads have individual personas, called Aameul and Hethradiah. They strive to dominate (and even kill) each other, but are unable to because they are aspects of one another. But despite that, many of Demogorgon's plots revolve around either permanently separating or uniting these two personas.
Demogorgon can hypnotize with a gaze or drive enemies insane. His whip-like tail has the ability to drain the life energy right out of a living foe. His tentacles cause living creatures to rot away, as if by some sort of rapid leprosy.

His title as Prince of Demons is contested and somewhat misleading in that in the chaos of the Abyss there are no official titles and positions. He holds this title through sheer power and the fact no other demon has been able to prove themselves his superior and wrest the name from him. Demogorgon is also known as Lord of All That Swims in Darkness.

The hatred between Orcus and Demogorgon is legendary. He is also a dedicated foe of both Graz'zt and Fraz-Urb'luu. Some of his allies include the Succubus Queen Malcanthet; the currently imprisoned succubus Shami-Amourae was his former consort.

Demogorgon lives on the 88th layer of the Abyss, known as Abysm, the Brine Flats, or Gaping Maw. This is a layer consisting of a great sea of briny water broken by tall, sharp, ugly, rocky prominences rising out of the endless murky water into a sky of yellow mist. Demogorgon's palace is two twin towers shaped very roughly like tightly coiled serpents that are covered with sharp, ugly fin-like features and spines, and crowned at the top with skull-shaped minarets. The two towers are linked by a bridge near the top. Beneath the fortress are reefs and caverns where mirmyxicus , kraken and ixitxachitl dwell, constantly warring with each other and worshipping Demogorgon in his palace above. His towers are said to extend so far beneath the sea that it connects to the layer beneath him where he speaks with Dagon, an ancient, aquatic Obyrith demon prince.

Numerous isles dotted the layer, but they all resemble Demogorgon's palace: twin rookeries rising straight out of the sea and into the sky. The only significant landmass of the layer is a vast jungle-covered continent. Here, Demogorgon's capital city of Lemoriax is located.

At the beginning of the battle:

the good guys were composed by Felenthir (sun elf divine emissary of Corellon :thumb45785261: ), Farn (half human-half shadow dragon sorcerer/bard [link] ), Sander (grey elf abjurer/incantatar [link] ), Vee (salt mephit and Farn's familiar), Uruk (half orc barbarian/legendary dreadnought), Tianor (dwarf saint/ cleric/contemplative/ hierophant of Moradin) , Soru (half elf paladin/holy fist/divine emissary of Ilmater), Loki (young-adult silver hidecarved dragon) and Isabella (human paladin/ divine emissary of Sune).

The bad guys were Demogorgon, a succubus anti-paladin of Shami-Amourae, a balor barbarian/frenzied berserk, a klurichir sorcerer, a marilith cleric, and a human bard/dirge singer.

At the climax of the battle (the moment that my pic shows) the only survivors were Felenthir, Farn (fully turned in his evil half shadow dragon form), the Dark Vee (the form of Shadow Mephit that Vee takes when her master Farn turns evil) and Sander, dominated by the hypnosis of Demogorgon and the power of the Vasharan charm.

In the end Demogorgon was slayed by Farn and his essence destroyed by the power of Sahandrian [link] , Felen's sword.