Complete Cthulhu, features the tales of Cthulhu Mythos by H. P. Lovecraft and Robert E. Howard.

Tales by H.P. Lovecraft
Nyarlathotep
The Nameless City
The Festival
The Colour of Space
The Call of Cthulhu: The Horror in Clay
The Call of Cthulhu: The Tale of Inspector Legrasse
The Call of Cthulhu: The Madness from the Sea
The Dunwich Horror
The Whisperer in Darkness
The Dreams in the Witch-House
At the Mountains of Madness
The Shadow Over Innsmouth
The Shadow Out of Time
The Haunter of the Dark
The Thing on the Doorstep
The Case of Charles Dexter Ward

Tales by Robert E. Howard
Arkham
Dig Me No Grave
The Black Stone
The Challenge From Beyond
The Fire of Asshurbanipal
The Thing on the Roof