Old Ones

Old Ones is a term used in fantasy games for the culture that was first on the scene in creation, before the limits of recorded history in the current setting of the game. This culture is always described as awesomely powerful, responsible for shaping entire landscapes, sinking continents beneath the waves, or giving birth to new races. An important feature of a race of Old Ones is they aren't around anymore -- or if they are, it's in some degenerate form (reduced to stone-age beasts, or a secluded colony hiding from the world, or one sleeping god-like individual).

Precursors is a roughly synonymous term, although it tends to connote less malevolence and more science fiction.

Call of Cthulhu

There were many "Old Ones" in the Cthulhu Mythos, and thus the CoC RPG. It's most commonly used to refer to one of the following two:

The Great Old Ones were alien beings of colossal size, and not exactly normal physics. All the Great Old Ones have been slain or imprisoned by Elder Gods, some entombed in planets like Earth. Some theorize that the Great Old Ones are imprisoned for the crime of practicing blasphemous black magic, and the Great Old Ones are just waiting to break out and avenge themselves. Others theorize the Great Old Ones submitted willingly to imprisonment, as a way to sleep away the aeons "until the stars are right" and they can resume their awful practices.

A shoggoth, D&D 3e style

The race of Old Ones (or Elder Things) were extraterrestrials that traveled between the stars, and set up a colony on primordial Earth. They built a city on the southern polar continent and experimented with the local biology to create a servant caste. Their discards were tossed to the other continents (the Cambrian Explosion?) and settled on their ideal lowest-class citizens: the Shoggoths, amorphous blobs of eyes and toothy mouths. The Shoggoths formed a rebellion and overthrew their masters, imprisoning them in suspended animation tombs of ice sealed with Elder Signs.

Forgotten Realms

Long long time ago, a lizardman type race had a huge empire that enslaved all the "warmbloods." It was probably the Sarrukh, mentioned in the Serpent Kingdoms splatbook. They're supposed to be extinct now, but it would make a decent BBEG. The Story of the First NeverWinter Nights explored this but made it all very confusing and disappointing.

Warhammer Fantasy

Psychic frog men from beyond the stars; they put a warp-gate at each of the poles and shifted the planet's orbit to something nicer for their amphibian biology. All that's left of them in present day are the degenerate & decadent rulers of the Lizardmen armies, the Slann.

In old editions of 40K and WFB, these were the same Old Ones as the Old Ones below. In fact, the newest edition of the WFB rulebook specifically mentions their big silver space-ships, suggesting that that's still the case.

Warhammer 40,000

The Old Ones were an extremely advanced and powerful tech-sorcerer race of beings (probably lizardmen) back when the grass was green, the Warp was nice, and the Emperor wasn't born yet. They made other races like in that vidya gaem Spore.

Then they met the Necrontyr, and all hell broke loose.

The Necrontyr, being miserable piles of shit with miserable short lives envied the Old Ones and started to war against them.

The Old Ones fucked them seven ways 'till Sunday until the Necrontyr, who realised they were not strong enough to win, discovered the Star-Gods, the C'tan, sort of ghostly star vampires made of ethereal matter. They had no idea what the warp was.

Blah blah sacrifice our souls and live as cold metal automatons blah blah fight the Old ones.

The C'tans said, "No Necrontyr, YOU ARE THE NECRONS." And then Necron was a grimdark.

At this point the Old Ones supposedly created other races to RAW RAW fight the Necrons: The Eldar, the Orks and the Jokaero which are like Space gorillas like that movie Planet of The Apes, but thought humans should just be evolved a little, with psykers being rare. That's right, mutant psykers suffer because they are far too marginalised in the gene pool, shunned by society due to awkwardness and so the Imperium suffers. Well done Old Ones, well done.

Why the frick did you make the goddamn sphess elves out of us if you were gonna cut off our metaphorical dick afterwards?!!

All the galaxywide genocides made the then-silent Warp into a copy of Catholic Hell, all full of FIGHTAN, KAY-OSS, DEMONS and FAIL.

In the end, the Necrons and their C'Tan overlords were forced(?) into hibernation when Enslavers, complete Krell and Illithid rip-offs came out of another dimension and buttfucked every last Old One and 99% of their minions. The C'tan went hungry, and the new and young races survived when all Necrons went to sleep.

The Old Ones themselves, seeming to have done one Acid strip too many, promptly disappeared from the scene, except playing the video game Spore. Fuck off you shitcunts, all the grimdark and fail is your fault.