Who needs a 4th squad member…
The fog effect in PUBG is really fantastic, and changes so much in terms of how you play the game. Sniping is greatly reduced, close quarters combat is far more common, and mid-range combat is full of new unknowns.
Areas of the map you normally have a great view from you now likely don’t, and previous spots that left you too open can work because the fog limits how far you can be seen.
Great addition, and I wish it occurred more often, or replaced the damn rain.
Hardcore Casual 
I love the rain, you take that back!
What, why?
After every rain game my head feels like it got stomped on for 30 minutes.
I like it because I can stomp around like a mad man and not worry about people hearing me.