"Eternal Darkness: Sanity's Requiem" is a survival horror video game developed by Silicon Knights and released for the Nintendo GameCube in 2002. The game follows the story of Alex Roivas, who investigates her grandfather's mysterious death and uncovers an ancient evil. Players navigate through various time periods and locations, solving puzzles and battling enemies influenced by Lovecraftian horror. A unique feature of the game is its "Sanity Meter," which affects gameplay as characters experience psychological effects from encountering supernatural entities. As the meter decreases, players may witness disturbing visual and auditory hallucinations, enhancing the game's eerie atmosphere and sense of dread.