Konstantin Tsiolkovsky, Astonishing Swordsmen & Sorcerers of Hyperborea's Ghost Ship of the Desert Dunes & S3 Expedition to the Barrier Peaks By Gary Gygax

"Somewhere in the depths of Diamond Desert lie the skeletal remains of Ymir’s Serpent, a legendary Viking longship. In days of yore, Sigtrygg Forkbeard led his company upriver, piercing the desert’s hostile heart. There the Vikings unearthed a lost mine brimming with green diamonds, but the River Æolus desiccated as the Serpent prepared for launch, and the ship was swallowed by the dunes. Forkbeard and his company were never seen again, but tales of a shimmering Viking ghost ship gliding over the dunes persist to this day."

Ghost Ship of the Desert Dunes By Jeffrey Talanian is the one beginning adventure for Astonishing Swordsmen & Sorcerers of Hyperborea rpg that I'd run straight outta of the gate for getting a campaign off of the ground. Ghost Ship isn't really based on any one H.P.Lovecraft, Robert E.Howard, or Clark Ashton Smith story or novella per say. But its got my gears turning when it comes Konstantin Eduardovich Tsiolkovsky. Who was Konstantin Eduardovich Tsiolkovsky? Well according to his wiki entry;
"Konstantin Eduardovich Tsiolkovsky (Russian: Константин Эдуардович Циолковский, IPA: [kənstɐnʲˈtʲin ɪdʊˈardəvʲɪtɕ tsɨɐlˈkofskʲɪj] (listen); 17 September [O.S. 5 September] 1857  – 19 September 1935) was a Russian and Soviet rocket scientist and pioneer of the astronautic theory."
Its really Tsiolkovsk's book 'The Will of the Universe' that's got me thinking about certain aspects of AS&SH's Ghost Ship of the Desert Dunes;
"Tsiolkovsky wrote a book called The Will of the Universe. The Unknown Intelligence in 1928 in which he propounded a philosophy of panpsychism. He believed humans would eventually colonize the Milky Way galaxy. His thought preceded the Space Age by several decades, and some of what he foresaw in his imagination has come into being since his death. Tsiolkovsky also did not believe in traditional religious cosmology, but instead (and to the chagrin of the Soviet authorities) he believed in a cosmic being that governed humans as "marionettes, mechanical puppets, machines, movie characters",^[22] thereby adhering to a mechanical view of the universe, which he believed would be controlled in the millennia to come through the power of human science and industry."
What would happen if you had a sort of 'anti 2001' event happening upon Hyperborea's Diamond Desert? Imagine if you will that the cycle of the Great Old of Clark Ashton Smith's Hyperborea also marks other trans cosmic events. In this case an alien intelligence out in the middle of the alien desert of Hyperborea. Something infinitely more dangerous then would first appear. 
Maybe something truly alien has been using life forms out in the desert as merely pawns?! The events of Ghost Ship of the Desert Dunes By Jeffrey Talanian continue normally but after the adventurers find the adventure's conclusion. Something else is awoken by their stirrings in the sand!?!
One of the most dangerous & yet easily overlooked truly alien races in AS&SH is the Great Race of Yith.  The Great Race are from The Shadow Out of Time a novella  H. P. Lovecraft.

Written between November 1934 and February 1935, it was first published in the June 1936 issue of Astounding Stories.
"[T]he Great Race ... waxed well-nigh omniscient, and turned to the task of setting up exchanges with the minds of other planets, and of exploring their pasts and futures. It sought likewise to fathom the past years and origin of that black, aeon-dead orb in far space whence its own mental heritage had come – for the mind of the Great Race was older than its bodily form. . . The beings of a dying elder world, wise with the ultimate secrets, had looked ahead for a new world and species wherein they might have long life; and had sent their minds en masse into that future race best adapted to house them – the cone-shaped beings that peopled our earth a billion years ago.

— H. P. Lovecraft, "The Shadow Out of Time"


If one of the Great Races of Yith's techno occult bases was uncovered by the meddling of adventurers then the truly alien inheritors & time travelers from beyond the stars may have renewed their time  war upon humanity. Yes I said time war. The Great Race is beyond our standard comprehension but let's wax nigh for a moment. The Great Race has been warring with humanity for the destruction of their own timeline has been happening for eons.
What if for a moment here the that this war with the Great Race went full on hot? Could humanity deal with the fall out?! Imagine if you will a minor historical event that causes a space craft to crash land into a primitive world? You know like a space craft crashing into the Grand Duchy of Geoff just outside of the countryside of Hyperborea? Then those monsters started showing up?! 
"The Grand Duchy of Geoff has recently been plagued by a rash of unusually weird and terrible monsters of an unknown sort. This western area, particularly the mountain fastness which separates the Grand Duchy from the Dry Steppes, has long been renowned for the generation of the most fearsome beasts, and it has been shunned accordingly -- save a handful of hardy souls with exceptional abilities. Within the last few months, however, a walled town not far distant from the area, and four small fortresses as well, have been destroyed by mysterious attacks!"


The Great Race stands back & watches as the humans scramble & the introduction of the invasive Mind Flayer aliens again are introduced to another world! The fallout from such an introduction would be devestating to the local ecology! 


Unwelcome vistor via the artwork of Jeff Dee from SC3 Expediation
To the Barrier Peaks
Not only could the machinations of the Great Race of Yith go on for centuries undetected but the monsters would ravage the countryside of Hyperborea. Adventurers would have years of campaign time to clean up the land sharks,veggie pygmies, & other horrors.
All arranged by the Great Race!



Great  Race of Yith miniature from the Cththlhu Wars Game.
 Minature available here. 

All of this is to keep the PC's out of the Great Race of Yith's tendrils. The Yithians have a very large network of  underground library city bases across the underworld of Hyperborea. They use them to experiment on the population of Hyperborea using a variation of their standard mind swapping techiques. The other time traveling drug they use is a variation of Clark Ashton Smith's 'The Plutonian Drug'. Their trying to find the best route through the time streams to the local space time continuum using the human mind & soul. But the real reason is time properties of the  separation of consciousness that we'd see later on from the Martians of CAS's Mnemoka (1955).

The question becomes are some or all members of the Great Race of Yith part of the Tsiolkovsky's The Will of the Universe  or  The Unknown Intelligence? Or is it really this cosmic alien intelligence that their trying to escape by time jumping to escape from it?