I do not like to play horror or psychological thriller games, but Eternal Darkness is peak and has held up over time very well. The game play, puzzles, and eldritch-style horror elements blend perfectly in this near master piece of a game. This game also has a unique game play mechanic in it: sanity. As your sanity decreases from encountering monsters, the game will start to mess with you with hallucinations.
You play as and follow several characters that are all intertwined in a plot of the elder gods. Exploring various places around the world finding secrets lost to time with the only constant being the Tome of Eternal Darkness.
I have played this game many times and can not recommend it enough.