I was playing tranzit and I had ballistic knife with gavaknucles. So for a few rounds I was just knifing. And when the round was changing I was looking at the other player (public match-2players) with ballistic knife. And then suddendly a green mist appear like when u get a persistent perk (he said a line about it) but I didn't see any difference. I also played buried and had ballistic knife with gavaknucles and while I was knifing the green mist appeared again. Anyone knows wt is this?