Call of Cthulhu
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Call of Cthulhu is a roleplaying game based on the works of H. P. Lovecraft. The characters are investigators of the unknown in an uncaring universe filled with ancient horror and Things Man was Not Meant to Know. That the characters will eventually be driven insane is as certain as that Paranoia characters will eventually end up dead.
Call of Cthulhu is commonly played in one of three eras: The 1890s, the 1920s, and modern day. Games set in modern day frequently make use of the Delta Green supplement, which adds a global conspiracy aspect to the game and is widely regarded as being of excellent quality.