I found a very odd encouter before. You all know how sometimes when you fast travel enemies spawn and kill everyone at that certain location right? well three great kahns spawn by the toxic waste site between novac and nelson, by the legion assassin spawn area behind the hill. I was walking then they randomly spawned in front of me. I walk over the hill then the Legion Assassins spawn and i run towards the kahns to see if they would attack the legion but they didnt they instead, helped the legion to attempt to kill me but they all got owned by me and my companions.