The key here is the Norkers which in 'Old Earth' were/are workers for heavy gravity worlds mining for ores & other precious metals because of their exoskeleton frame work, tremendous strength, resilience, & outright tenacity. So they've been imported back to old Earth by the semi demonic/human hobgoblins. Norkers make perfect workers for Hell planets like Io.
Hobgoblins were developed from human races after 'the War of the Ancients.' Hobgoblins have been developed by the Ancients to form both a demonically bred military force & a race for sacrifice upon the altars for a variety of Lovecraftian gods. They've settled into the wastelands of what was once China & parts of the panhandle of the Orient. They rule over vast numbers of humans surrounded by human states that wage war back & forth with them.
The Gnomes which form the basis for part of the plot of 'The Forgotten Temple of Tharizdun' need a bit of a make over. They become Celts or Picts in this redress of I'm leaning far more toward the Picts end of the spectrum because of the Robert Howard connection. The Norkers are raiding their settlements & one time the Ancients used to sacrifice the Picts to the god thing Tharizdun.
Tharizdun was/is another old one from Saturn whose worship came back into vague just before the Great Plagues swept the Earth & its colonies throughout the solar system. But that was a very long time ago and its only recently that the vaults have been opened again.
The question is will the madness continue to spread across 'Old Earth'.
Well having run S4 The Lost Caverns of Tsojcanth By Gary Gygax yesterday for Privait Con 2017 it only seems natural that I'd turn my attention to one of my all time favorite Greyhawk adventures Forgotten Temple of Tharizdun By Gary Gygax. I've adapted it a couple of times but now I'm seriously looking into taking the adventure apart & adapting it into a campaign cornerstone.