The campaign is based in a sorcerer's tower somewhere in the deserts of Shem. The PCs are his hirelings and they don't know exactly where they are because he brought them here via a demongate from Arenjun. Having served him for a few years, this happens:
The tower stood, dark and menacing in the sweltering desert, casting a foreboding shadow upon the shifting sands. Like a massive fang it jutted hundreds of feet above the desert floor…jagged and unnatural it was, and feared by all who lived near it. The old ones of the local tribes, they could recall the tales of their grandfathers, tales of a time when no tower stood amidst the endless dunes. But then the sorcerer had come, a dark and sinister Stygian, his face jagged and angular like the tower he would build.
For years, summoned creatures did his dark bidding, wielding the power of the earth itself, molding the very bedrock into this massive spire. A few daring warriors were brave enough to challenge the invaders, but they were no match for the Stygian’s evil sorcery. Fortunately, the sorcerer, like others of his ilk, cared little for the trivial creatures that lived in the desert. So they left him alone, and he didn’t trouble them. Oh, from time to time a new generation of tribesmen would assault his tower, but they found only death beneath the dark spire.
And yet, though their efforts came to naught, the frightened Shemites’ fears of dark and unspeakable evil were well founded. For on the Night of the Jackal, the Stygian sorcerer, an ancient outcast named Thutmose-Sobek, made his way to his summoning circle in the bowels of his tower, bent on a diabolic scheme. In his company were a young man and woman, one an apprentice, the other a slave. The man was a Kushite Witchman, a powerful weaver of spells in his own right, and the slave was a former Stygian noblewoman, well versed in the sensual nature of demonic ritual.
The three took their places in the circle. The lamplight painted the sorcerer’s creviced face in an eerie reddish hue…his expression was that of a living corpse, nearly devoid of the emotions that had once made him human. The Kushite, equally frightening in appearance with his many tattoos and ritual scars, began to hammer a slow, pounding beat on his drum. The slave woman shed the tiny wisp of silk that was her only garment and began to dance, her shapely body moving with serpentine grace through the flickering lamplight.
Thutmose-Sobek’s deep voice filled the chamber, speaking an ancient and alien tongue…an incant that was first spoken when man’s ancestor’s had scarcely begun to walk upright:
“Gib, Thothnath, Yog Nashpur!” He chanted.
“Gib, Thothnath, Yog Nashpur!”
The slave and the Kushite both shuddered as the incant drifted across the stale, dry air. Though neither recognized the spell, the words betrayed it’s vile and inhuman nature. But both realized and feared the power of their master, and they did precisely as they were bidden.
“Gib, Thothnath, Yog Nashpur!”
The sorcerer lit a brazier. The smell of dried lotus petals from the tombs of ancient Acheron filled the room. He lit a second, and a third, and a fourth…each igniting a unique alchemical compound as the spell built towards it’s climax. The tempo quickened to a frantic beat, like the pounding heart of a sacrificial victim the instant before the blade is plunged into her heart. The slave woman spun and gyrated, sweat pouring down her luscious curves, moaning like a whore at the edge of ecstasy.
“Gib, Thothnath, Yog Nashpur!”
The fifth brazier was lit. Thutmose-Sobek’s serpent eyes gleamed with deadly fire…he had waited for decades to collect the knowledge…the components…the raw magical power to cast this spell. Far away, werewolves went on a killing frenzy, succumbing completely to bestial viciousness. Vampires the world over fed like starving animals, bathing themselves in the blood of their victims. And thousands cried out in fear as Set swallowed the moon.
“Gib! Thothnath! Yog Nashpur!”
A swirling mass of black tendrils began to form within the circle. The chant continued, now echoed by other voices…distant…chilling…inhuman. The slave and the witchman, in spite of their previous experience in things arcane and demonic, shuddered with apprehension as the nameless horror began to take shape before their eyes.
“Gib! Thothnath! Yog Nashpur!”
The ancient Stygian lit the sixth and last brazier. The black tendrils had now coalesced into a tangible darkness that swirled about in the circle like a living thing. Wisps of greenish smoke coiled about him as the spell reached it’s climax…and then, he caught the scent of something…something unfamiliar…and his dark eyes went wide with fear.
“My servants!” he cried. “Set preserve us! Flee!”
As the words left his mouth, a massive clawed hand burst forth from the darkness and seized Thutmose-Sobek, it’s talons rending robes, flesh and bone. The Stygian woman screamed in terror, recoiling from the horrific sight. The Kushite hesitated, torn by a desire to help his master and the knowledge that there was nothing he could do.
“Flee!” The sorcerer screamed. “I am lost! Fly before HE takes you! I shall wait for thee, my servants…in Hell!”
The slave needed no further prompting, and the Kushite was close on her heels. The tower quaked as lightning gashed the heavens asunder. Hideous, gibbering laughter echoed through the tower and across the swirling sands. Storm clouds appeared from nowhere and blood fell from the skies. A terrible cry echoed through the halls, and Thutmose-Sobek was gone.