Interesting point, Kedjane. I think that most devs of today just don't understand what really makes a scary game. As H.P. Lovecraft himself once said, fear of the unknown is the greatest fear mankind has. I think that's very true. Most horror games of today explain too much. Penumbra didn't and that's something I love about the game.
If Unknown does have weapons, I hope they're done like some of the weapons from a little known horror game called Nosferatu Wrath of Malachi. In that game, the player used period weapons from the late 1800s, including a single shot musket. There was a great sense of panic and fear when you saw a monster, shot, missed with your one bullet, and ran around desperately reloading for another single shot.
Frictional, PLEASE use period weapons from the 1700s if you use weapons. No machine guns, shotguns, rockets, lasers, missiles, or grenades. But really, I would prefer no weapons at all anyway