Other contenders: I Have No Mouth, And I Must Scream Dead Space Nier Drakengard Silenthill 1-3 Manhunt 1-2 The Witcher Franchise Planescape Torment Dragons Dogma Demon's/Dark Souls Gothic Darklands Metro 2033 (the book is almost suffocating) STALKER L4D TWD
That's all I got right now. But forgetting Nier guys? C'mon...Game is so dark.
I don't think 90% of these people have heard of Nier, let alone played it. But yes, that game is depressing as crap. Beautiful music though.
And Warhammer 40k is pretty bad too. Billions die at the drop of a hat.