I love how I completely failed to notice that I started mis-numbering sessions. 6 comes after 5, not (immediately) after 4! Numbering has been corrected.
Upon discovering the secret passageway leading down in the ancient Hyperborean tomb buried within the Ettowah Mounds, the PCs began their descent down the steep, narrow stairway, which eventually opened up onto a long, narrow room, some 30 feet long by 15 feet wide. Examination by torchlight revealed the walls to be covered with frescoes and bas-relief carvings, and the floor to be made up of hexagonal tiles, three of which bore incised runic symbols chased in copper.
Wisely, they decided to poke one of these symbols with a stick, causing it to throw off a shower of blue-white sparks. Upon discovering that all three symbols did the same thing, Dr. Ryder decided to slap his hand down on one of them, resulting in a significant electric charge coursing through him and paralyzing his muscles until Nashoba knocked him away from the symbol with a stick.
Here's where the silly began, because at this point Nashoba's player suggested that Dr. Ryder might gain electrical powers from the exposure, a la the film ERNEST GOES TO JAIL. In a good mood, I decided to go with it and assigned a 1% chance of Dr. Ryder carrying a permanent electric aura, which could be discharged at will through his hands.
He did not get lucky on that roll.
However, this is where Dr. Ryder's player began to exhibit some disturbing mad scientist traits. In an experiment designed to shock the "souls" sane, he placed the alien canister containing the persona of Robert Griner on one of the symbols. The canister began to vibrate and shake before blowing its lid off in a gout of oily steam. Looking inside, they discovered that the canister contained a now-cooked human brain, presumably that of Griner, and that the other two canisters likely contained the brains of Priscilla Griner and Meriwether Lewis.
Dr. Ryder began contemplating removing the brain from one of the dogs they'd brought with them, placing Meriwether Lewis' brain in the dog's skull, then using the symbols to shock the resultant entity back to life, hopefully restoring Lewis to both life and sanity, just inside a dog's body. It was only the realization that a dog's skull is much smaller than a man's that prevented Dr. Ryder from following through on this idea.
Continuing on, they found themselves in an octagonal chamber containing rows of stone shelves, upon which were carefully stacked (kept neat by sitting in grooves carved into the shelves) silvery, jointed rods of various lengths, assorted pulleys, coils of silver chain, and several different sizes of parabolic mirrors and carefully polished glass lenses.
As Dr. Ryder began to examine these pieces and making notes on how they might be assembled into a machine, the air in the chamber began to move, and in a far corner, space began to warp, allowing a 12-foot tall alien creature to step into the room. Superficially resembling the bug-like creatures they'd encountered thusfar, this entity was significantly larger, with an enormous "brain" for a head, no visible wings (though the fact that the air behind it was blurred and it was floating a foot off the ground suggested that it may have been hovering like a hummingbird), and clutching a silvery, musket-shaped conglomeration of coiled tubes.
"I must congratulate you," the entity buzzed, "I did not expect any members of your species to have come as far or to have been as successful in opposing my race's plans as you have been. You've killed a few of my drones and developed a degree of understanding of what awaits your world. Well done. Of course, in the end you will ultimately fail, and this world will become another colony world, another stepping stone in the expansion of my kind's manifest destiny. But until that time...you entertain me. And I am willing to be - what's the word your kind uses? - sporting. On that wall, " the creature gestured with one claw, "are instructions for the ritual with which I will summon Shub-Niggurath and allow my kind to breed in great numbers upon the Earth. You have paper, charcoal with you, I assume? Make a copy of the ritual. Decipher it. Study it. I want to see if you can find a way to stop me from overrunning your planet. You have until the rising of the full moon on October 31st of next year, by your calendars. At that point, all will be complete and your world will become mine. Good luck."
The creature began to phase back into whatever dimensional pocket it had emerged from, taking the various parts from the shelves with it through a mere gesture. Liza tried to blast the creature with her blunderbuss, but it reacted faster than she could and shot her with a gout of unbearable cold from its "musket." She fell back as the entity, and the parts, vanished.
Once Liza thawed out, they copied down the ritual scribed on the wall - in Ancient Hyperborean, of course - and began making plans. They decided that the creature's plans must involve the giant mounds at Cahokia, near St. Louis, and prepared to set out in that direction after sending a quick update to Thomas Jefferson and asking him to meet them in St. Louis.
Along the way to Cahokia, they poked through every mound they passed looking for another set of those parts, as Dr. Ryder was convinced he could assemble them into whatever it was they assembled into. They did not find any. Meanwhile, Liza began studying the book they'd found at the Griner homestead in earnest - discovering it to be a first edition copy of Monstres & Their Kynde, written over a century and a half earlier and detailing a great deal of information about demonology and summoning and controlling the entities of the Invisible World.
Arriving in St. Louis, they immediately began poking around Cahokia, or Monk's Mound as it's being called since a small monastic group settled near the top and began farming there. Questioning a monk revealed little, but poking around on their own led the PCs to discover copper arrowheads and a stone tablet with a few half-legible Hyperborean runes (still untranslatable to them, by the way) visible. Finally, while investigating a suspicious patch of fungal growth near the base, the growth erupted in a spray of choking spores - knocking Liza and Nashoba unconscious.