Star-Spawn

The Star-Spawn are a group of creatures written about in various texts on Terra and by Mordenkainen on Oerth in Greyhawk.

Name

Their name is spelled star spawn by Mordenkainen, Star-Spawn by Howard Phillips Lovecraft, and Star Spawn or even Starspawn by various other writers. They're also called the Star-Spawn of Cthulhu, the Cthulhi, or the Xothians.

In the past, they've been called (or perhaps simply equated with) the Foulspawn.

History on Terra

It is said that the Star-Spawn of Cthulhu arrived on Earth sometime after the Elder Things did (more than 1 billion years ago) and likely before the arrival of the Flying Polyps (600 million years ago). They are said to have come from some far-off region of space, or from another dimension entirely. They fought wars against the Elder Things, eventually arriving at some kind of armistice and a division of territory.

In At the Mountains of Madness, the narrator, Dr. William Dyer, describes an alien race (who looked vaguely octopoid) who came down to the earth from "cosmic infinity" to wage war on the Elder Things. Dyer himself says that these alien octopoids and the Star-Spawn of Cthulhu are probably the same beings, so most other occultists, xenobiologists, and other scholars just assume the Star-Spawn look very squidy. They're often portrayed as looking like tiny Cthulhus, so that's kinda fun.

In D&D and PF

On Oerth and Toril, the Star-Spawn have taken up the servitude and worship of other entities, namely the Elder Evils, such as:

• Borem of the Lake of Boiling Mud
• Atropus, the World Born Dead
• Haask, the Voice of Hargut
• Tyranthraxus, the Flamed One
• Tharizdun

In Pathfinder, the Star-Spawn are indeed followers of Cthulhu. They are omnicidal, and wish to expand the Dark Tapestry by eradicating life on every world. Their modus operandi is sending visions to "susceptible individuals" and seeding apocalyptic cults, which they then call to arms when the stars align to systematically exterminate all life on the planet (including their cultists, whom they reward by killing last).

I'm not sure why Cthulhu wants this, but hey, he's the big squid, not me.