I would personally enjoy having the yellowish background when using feral instincts again. I did not feel it was OP, would have made for a nice upgrade for the armory to purchase the ability to have it go back to normal or for those who don't quite care much for feral instincts, they can choose to not purchase it. I am still caught of guard by my lack of knowledge of leper spawns, which I know is my own issue and should be able to figure out quickly, but it changed right when I was trying to learn all leper spawn locations haha. Bad timing on my part. Oh well, just my 2 cents!
I have never got no challenge showing up on any game. Like i said i get completionist almost every game 55 out of the last 60 games i have played i have gotten completionist. My per game stats are now 10.11 challenges completed per game.
Why do you? Oh, you like to show off... I see.
I never tell people what two classes I am running (or the fact I have everything + lots of spare teeth) unless they ask me questions. If they start asking "do you have this upgrade and that upgrade", I simply respond with a "I have everything" - it's a lot easier and quicker, rather than have them go through the list of upgrades asking if I do or do not have them.