Cthulhu is one of the Great Old Ones. He is currently dead, and lies sleeping in his house at R'lyeh. We really don't want him to wake up.
Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn!
Iä! Iä! Cthulhu fhtagn!
Cthulhu R'lyeh fhtagn!