Sally makes landfall in Florida on September 19. She’s been a Category 3 hurricane since the 17th. Sally carries a Formless Spawn of Tsathoggua, sucked out of an underground temple on Mayaguana by 125 mph winds.
The Spawn is deposited in pouring rain near Lake Okeechobee. Almost by accident, it kills six people in Carlson’s Mobile Home Park. That’s right outside Pahokee, on the southeast shore of the shallow lake. It gorges itself on the contents of a septic tank, then follows the murky flood waters.
The Spawn can be tracked by the extreme acidity of the water where it’s holed up in Pelican Bay. Given time, it will migrate through the agricultural canal connecting to the Miami River, likely killing dozens of the unbelievers that surround it in Miami, before escaping into the Atlantic and oozing back to Mayaguana.
The Spawn is not in any great hurry. On the marshy southern rim of the lake, there are three islands—Kreamer, Ritta, and Torey—long since abandoned by the pioneers that settled them in the 19th century. The Spawn nurses its wounds here, in the ruins and the bulrushes. This is where Delta Green finds it.
This was an entry in the 2013 shotgun scenario contest, written by Viktor Eikman.