Now I don't know if this is something anyone else is experiencing but listen to this.
On the 12th day of my newest survival run through I decided to venture out of my home base at trappers cabin and set up supply locations in Forlorn Muskeg. (I did this so the journey between Bleak Inlet and Mystery Lake would be safe in the case of a spontaneous blizzard). On the 14th day I was leaving the forge in FM and I took a shot at a wolf but it wasn't fatal so it ran away towards the tracks, I let it go because i figured I might find it later after it bled out (either way it wasn't worth the ammunition). Not to long later I took down a bear and spent until nightfall to make sure I got everything I needed from the carcass. I wanted to keep moving through the night so I could deploy my rope at the ravine and then find a safe place to spend the rest of the night. At about 3 hours after nightfall I approached the tracks I noticed a wolf standing perfectly still in the middle of an ice patch. I pulled out my rifle aimed it at the wolfs head. I carefully aimed. I took my shot. Nothing. The bullet seemed to pass though the wolf's head. Even if had simply missed my shot the wolf would have run away from the mere sound of the shot but nothing. The wolf stood still. At this point one of the creepier music tracks started playing and I got genuinely creeped out and scared for one of the first times ever playing this game. I had gotten to the point where I wanted to run into the wolf just to see if it would attack or react in any way, but I couldn't. The wolf was surrounded by weak ice. I took more shots at it, aiming straight at its body and aiming carefully, but the bullets just passed through. All I can say is that I will not be hunting any wolves for a long time, as the last thing I need is an army of undead wolves following me for the rest of the long dark.