Teaming with the murderer is against the PartyZone rules, though it does depend on the situation. For example, if you are your friend are playing murder and both of you are bystanders, you are allowed to team then as long as you don't ghost. If however, one of you turns out to be the murderer the next round, and you still team, that is not allowed and will be punished if caught. Letting the murderer kill everyone to save you last, is also considered teaming, even if you do kill the murderer afterwards. I hoped this cleared some things up.