Vex (I have only been in a few parties and fireteams) it was a bit touch and go about what they were going to call me and they desperately tried hard to avoid the obvious. At one point one of the guys was like so Imma gonna call you vex. Which worked out nicely, It's much easier to shout "Hey vex you're totally going the wrong way" or "Vex you should probably aim" Then VUCK.