Sequel to Penumbra Requiem?

[Kedjane]

A sequel could be about a person arriving to investigate. If he sent it to a friend perhaps the friend goes "Huh? Kill who?", travels to Greenland to investigate and such. Perhaps he wouldn't take the warning seriously or perhaps he would bring a personal firearm like some common 9mm pistol with only one spare magazine or something like that which the player would have to conserve for the entire game.
Then you could encounter monster dogs and all such - which would go down in just one or two gunshots but if you waste your ammo on killing enemies you won't be able to kill harder enemies later in the game (or will have to kill them in a much harder fasion, melee for example). Also it would be pretty interesting if the gun could be used to solve puzzles, so instead of stacking lots of stuff, climbing to some high place and deactivating a switch you could shoot the switch so that it breaks or instead of cutting a rope using a knife you could shoot the rope from a distance - solving puzzles faster or skipping hard parts of the game in case you didn't use your ammo on the enemies.
Weapons could be a like a "skip level" pickup in old games instead of being just for killing enemies.

Example: the player comes into a room full of storage boxes looking for Item X, but the box that contains Item X is currently being held up by one of many mechanical cranes (err, not the animals). So the player could either activate the controls for the cranes and position the boxes in the air so that he can climb up on the first box and jump to the next one until the comes close enough to the box containing Item X so that he can cut it down with a knife or something.
However if the player doesn't manage to solve how to activate the cranes or something instead he can just fire the gun at the box so it falls down, breaks and Item X is released.

It could also be used for getting past hard bosses more easily or kill chasing enemies, instead of the player having to cheat to get past that part of the game etc.

This way the firearm would keep it's power, but still wouldn't ruin the game and would only have to be used if you wanted to and really was stuck - instead of getting frustrated and not playing the game.