
The Red Mist blocking your path that you occasionally encounter in Redfall is not just a visual barrier, it’s also toxic. If you venture into this fog, you will start to take damage rapidly. So you must either avoid it entirely or find some form of protection or countermeasure to safely navigate through it.
Don’t worry though, the solution is surprisingly simple!
Clearing the Red Mist
When you come across bloodbags that are surrounded by a cloud of red mist, watch out. Shooting at these enemies is pointless because it does nothing to them. The trick to beating these enemies is using Ultraviolet light. All you have to do is point a UV beam at them using the UV-102B Medusa.

The UV beam clears the mist spewed by the bloodbags momentarily, which allows you to either kill them with your weapon (AR, Shotgun) or lets you get close enough to melee. BTW, the UV lightray gun (UV-102B ‘Medusa’) is also great for freezing Vampires in general while also inflicting considerable damage.
Getting the UV-102B Medusa is pretty straightforward since you are bound to find it on the path to completing your main mission. However if you were unlucky and seem to have missed it, here is where you can go find it.
UV-102B Medusa location
During your first mission, you must have come across two crash sites. The second of these two crash sites (helicopter crash site) has two UV-102B Medusas – a level 1 and a level 2. See below image for location on map.

Beware!
There’s one another kind of Red Mist in the game. That which is caused by bombs with the cultists throw. Sadly, you can’t clear that red mist with UV beam. For that, your best bet is to dodge and wait for the mist to disperse on its own.
Here a video of the UV-102B Medusa in action (courtesy of youtuber Admiral Vic).