[From a fragmentary transcription of the sixth Latin edition of the Chthonic Chronicles, believed lost during the great fire of London in 1666:]
"O', great and luminous ones, who came from beyond the stars to slumber serene beneath the earth of the third sphere, hearken to me!
Hear me, o' mighty one, o' great Khthon!
Awaken and hear my adulation, o' divine and glorious God of gods!
From thy hoary tomb thou shalt ascend, and the earth shall be enraptured by thy majesty!"

"Khthon!
To the ancient Lemurians, you assumed the guise of a beautiful azure-skinned woman with great black wings, to the Atlanteans, you manifested as a brilliant fiery sphere of searing radiant energy, to the peoples of Ultima Thule and Hyperborea, you took the form of a titanic crystalline dragon.
Yet your true form is beyond the ken of men, darker than the blackest heart of deepest night, more terrifying than the very essence of fear itself... thou art terror incarnate!
From the timeless void you came, son of Z'xulth!
Glory to They-Who-Lurk-And-Breed-In-Limbo!"

[Excerpts from translator's cautionary notation:]
"Behold these repositories of fearful arcane knowledge, tomes of aeons-old cursed lore which was surely ancient even when the ill-fortuned antedeluvian civilizations which initially articulated it first committed such dread lexicons of terror to shuddering memory!
Fear these legendary encyclopaedia antedeluvia, these ebon necronomica of shunned rites and diabolical adulations!
The Tome of Shadows, the Forbidden Books of the First Cataclysm, the Epsilon Exordium, the Scrolls of the Third Circle, the Oracle of Antediluvian Blasphemies, the Diabolist's Lexicon, the Arcana Atra Libri, the Thirteen Cryptical Prophecies of Mu, the Manuscripts of the Cultists of Ur, the Chronicle of Shadows, the Black Bible of Kor-Avul-Thaa, the Ancient Book of the Six Keys, the Cydonia Manifesto, the Index Librorum Prohibitorum, the Star-Maps of the Ancient Cosmographers, the Cursed Books of the Z'xulth, the Praxeum Codex, the Chthonic Chronicles!
I now know that there is something inestimably evil at large throughout the cosmos.
It is a ravenous and pitiless storm which rages across the universe, permeating the very fabric of creation, existing simultaneously in all dimensions, wholly unconstrained by linear time.
This force is the black, quasi-sentient mana which sustains such ageless revenants of the Z'xulth as the dread Dwellers in Eternal Shadow and the unspeakable They-Who-Lurk-And-Breed-In-Limbo.
When beings whose essences are intrinsically malefic choose to embrace this darksome energy source, the resultant sinister symbiosis can be sublimely diabolical, as evidenced by the black blight that was the infamous pseudo-human sorcerer Lord Angsaar!
And of course, the malign Zurra, that abominable result of an experiment by the Ersatz Ones gone disastrously wrong; an ill advised attempt to clone the K'laa genetic template of mighty Zuranthus in the Mera spawning vats beneath the Pre-Cambrian sea, only for the matrix to become contaminated by the errant cells of a captured fiend of Z'xulth!
The result was a prime fiend whose capacity for evil and wanton annihilation was exceeded only by a penchant for self-agrandizement and his rampant psychological instability.
In many cases, the potential for ruination and domination that such entities may aspire to is constrained only by their own physical and psychological limitations, as the toll which the dark mana takes upon the host's mind and flesh is not insignificant..."