A prolific horror game based on the works of H.P. Lovecraft¸ where PC's are investigators into the unknown who deal with horrors beyond comprehension. The basic game is set in 1920's U.S.¸ but there are also well-supported lines for 1990's U.S. and 1890's England. It uses the Chaosium Basic Role-Playing system¸ with the notable addition of ""Sanity"". Sanity is a percentile stat which is damaged when encountering grotesque or other-worldly things. It can be regained only with difficulty: by psychiatric treatment or by knowing that horrors have been defeated. It also has a maximum that is the inverse of your ""Mythos Knowledge"" skill (max SAN is 100-skill)¸ so the more you know about the truth the less sane you can be. Character creation involves random-roll attributes and percentile point-bought skills. - A description from https://darkshire.net/jhkim/rpg/encyclopedia/ with kind permission of John H. Kim"