Ogień przyjacielski? Nigdy o tym nie słyszałem.

The achievement for no friendly fire is bugged. I didn't shoot teammates in a couple of missions, but have yet to get the achievement. My friend was also trying for it, and didn't get it either. If you go to the full video for the last mission you can watch through. Often, I'd sit in a corner with my blade to make sure I did no damage. Thanks!