Warhammer 40,000

In the fictional universe of Warhammer 40,000, the Old Ones traveled through space and manipulated minor species on several planets to grow into tools for their battle against the C'tan. The Slaan were probably their servants.

Lovecraft's Cthulhu Mythos

'Old Ones', or Elder Things, are also a fictional species in the Cthulhu Mythos, first mentioned in the novel "At The Mountains of Madness " by H. P. Lovecraft, described in vivid detail. These aliens created cities beneath Antarctica during prehistory, and created the Shoggoths, a slave race.

Shoggoths are featured in Chaosium's and Wizards of the Coast's Call of Cthulhu role-playing games, and recently made in plush figures.