These are the Great Old Ones who play central roles in The Weird of Hali and its tentacular kindred. (Yes, I know, some of these are considered Outer Gods or Elder Gods in other versions of the mythos, but not here.) There are other Great Old Ones in my fictional world—several hundred active on Earth, and unimaginably many in the cosmos as a whole—but this is the cast of divine characters readers of the series will want to have in mind.
The eldest of the Great Old Ones, a bubbling primordial chaos inhabiting a realm of being incomprehensible to humans. Does not manifest on Earth except under very special conditions, but forms the backdrop to the entire cosmos. Servitors: immense lumbering flute-playing beings of indescribable shape. Worshiped by: some witches. Form usually encountered: nothing you can possibly imagine.
The Gate and the Guardian of the Gate, a being who spans all space and time; the father, grandfather, or great-grandfather of most of the other Great Old Ones on Earth. Servitors: none. Worshiped by: some sorcerers, the Starry Wisdom church, the Tcho-Tchos. Form usually encountered: floating luminous spheres that reflect the entire universe.
(Yeah, I know, Lovecraft spelled it differently, but then he could never miss a chance to slip in a racial slur.) The Black Goat of the Woods with a Thousand Young, the great mother goddess of Earth, she can also manifest as the Black Ram with a Thousand Ewes. Most of the Great Old Ones are her offspring or descendants. Servitors: the Dark Young of Shub-Ne’hurrath, massive treelike beings with heavy legs below their huge bodies, and a forest of tentacles above; also the Thousand Young, who are humans or other intelligent beings strangely reshaped by Her power. Worshiped by: pretty much everybody. Forms usually encountered: often puts on the appearance of an old woman, but may also be seen as a gigantic faunlike shape, female, with horns and shaggy hips and legs.
The Lord of the Great Deep, he is not strictly speaking present on the Earth, but rules all movement to and from other realms of being, including the Dreamlands. Servitors: Night-gaunts. Worshiped by: some sorcerers, families descended from the people of drowned Poseidonis. Form usually encountered: a vast midnight-black male form, hoary and bearded, with eyes like moons.
The high priest of the Great Old Ones, the only one among them capable of invoking those powers as far beyond the Great Old Ones as they are beyond human beings, Cthulhu lies, “dead yet dreaming,” in his temple-tomb in drowned R’lyeh until the stars are right. Servitors: Cthulhu-spawn, who are wingless but otherwise resemble him, and Deep Ones, who are aquatic hominids closely related to humans. Worshiped by: the Deep Ones, the Esoteric Order of Dagon, families descended from the people of drowned Poseidonis, the Starry Wisdom church, the Tcho-Tchos. Form usually encountered: he hasn’t been encountered awake since the end of the Cretaceous period, but when he rises from the sea at last, he will be a titanic bipedal figure with great dragonlike wings, many eyes, and tentacles descending from the lower half of his face.
The Wind-Walker, lord of the world’s frozen places, Ithaqua is the god of limits; he is half-brother to Cthulhu and full brother to Hastur. He strides through the air and is accompanied by tremendous cold. Servitors: the gnophkehs, monstrous six-limbed hunters of the frozen wastes. Worshiped by: nobody. You respect Ithaqua, but you don’t invoke him. Form usually encountered: a gigantic, gaunt, naked human figure with flowing white hair and a long white beard, most often seen stalking through the sky; his eyes burn red like coals.
The King in Yellow, ruler of the Great Old Ones on Earth, he dwells in the City of the Pyramids in far Carcosa. His face has been hidden behind the Pallid Mask for sixty-five million years. The Yellow Sign is his emblem. Servitors: the Fellowship of the Yellow Sign, an order of humans and other intelligent beings who are sworn to his service. Worshiped by: the Esoteric Order of Dagon, families descended from the people of drowned Poseidonis, the Starry Wisdom church, the Tcho-Tchos. Form usually encountered: tall and thin, pallid white in color, with flowing white hair. His face is covered by a mask the color of ivory; his hands have six fingers each; he wears tattered and scalloped robes of yellow.
The Lady of the Beasts, she was worshiped as an elk goddess in old Hyperborea and has special rulership over all mammals. A daughter of Shub-Ne’hurrath by Ithaqua. Servitors: all wild animals. Worshiped by: families descended from the people of drowned Poseidonis, the Starry Wisdom church. Forms usually encountered: a winged elk, or a young woman with elk’s antlers. She can also take human forms when this is convenient.
The soul and mighty messenger of the Great Old Ones, the One in Black is coeval with Azathoth and Yog-Sothoth. He is the Black Man of witchcraft lore, the crossroads devil of blues legend, and the messenger of the gods revered in many ancient faiths. Servitors: witches, human cultists, silent black dogs who appear and disappear as he wills. All animals obey him. Worshiped by: everyone who reveres any of the Great Old Ones. Forms usually encountered: a very tall man of Egyptian appearance, dressed in a long black coat and a broad-brimmed black hat. In the Starry Wisdom church, he also takes the form of the Watcher in Darkness, a bat-winged horror with a three-lobed blazing eye.
The god of sorcerers and lord of voor (the life force), Tsathoggua is the oldest of the Great Old Ones on Earth. He dwells far underground and works mostly through his servitors, and through human sorcerers that venerate him. Some of his human worshipers call him Saint Toad. Servitors: voormis, who are prehuman hominids who dwell underground, and the Formless Spawn of Tsathoggua, pools of fluid black shapelessness that eat Tsathoggua’s enemies. (According to the Pnakotic Manuscript, shoggoths were created by the Elder Things in imitation of the Formless Spawn.) Worshiped by: families descended from the people of drowned Poseidonis, the Starry Wisdom church, the Tcho-Tchos. Form usually encountered: an odd, huge, somnolent form, rather like a toad, something like a bat, a little like a sloth, with glowing red eyes usually half-closed.
The youngest of the Great Old Ones on Earth, just nine million years old and so little more than a hatchling, Phauz is the daughter of Shub-Ne’hurrath by Hastur. She will be Queen of the Great Old Ones on Earth in the far future, when Hastur and Cthulhu have both withdrawn into contemplation. Her emblem in Hyperborean times was a woman-breasted cat. She is the mistress of cats; what any cat anywhere in the world knows, she knows. Servitors: cats. Worshiped by: families descended from the people of drowned Poseidonis, witches. Forms usually encountered: a cat, or a cat lady of indeterminate age.
Alongside the Great Old Ones stands another being who is not one of them, and so doesn't have a spot on the diagram, but has similar powers and characteristics. Back in the early Triassic, the Elder Things—a race of extraterrestrial critters who settled what is now Antarctica and several continents then nearby—set out to create a being comparable to the Great Old Ones but under their control. Their work succeeded rather too well, and the resulting entity—Nyogtha, The Thing That Should Not Be—rebelled against them. While he was defeated, he could not be reduced to subservience, and he fled into the deep places of the Earth. There he conspired with the shoggoths, the slave species the Elder Things made in imitation of the Formless Spawn of Tsathoggua, who had attempted unsuccessfully to win their freedom in the late Permian. The result of that conspiracy was the total extermination of the Elder Things. (If this suggests to you that Nyogtha is not an entity to mess with, why, yes, that's what it suggests to me, too.) Nyogtha remains active on Earth, and his pact with the shoggoths remains firm, so he can be added to the list above to make an even dozen:
NyogthaKnown as The Thing That Should Not Be—the Elder Things called him that, and he adopted the title as a gesture of defiance—and the Dweller in Darkness, Nyogtha lurks in the deep places of the Earth and pursues intricately plotted plans of his own. Servitors: shoggoths. Worshiped by: shoggoths, and also small cults of human witches. Form usually encountered: sheer impenetrable blackness.