Both the Penumbra series and Amnesia were very good. In Penumbra Overture,
but there was still a lot of tension build-up and chase scenes, which were always horrifying. In particular,
In Black Plague, just the idea of
and
was really scary, but the ending was too weird. I didn't play Requiem because it doesn't have a story.
In Amnesia, the tension is always there, and there are plenty of triggers to worry about (like if I pull this lever, what should I do if a monster jumps out?) But
So it's hard to say which game is scariest. I liked the story of Amnesia more.