A few times in Halo 4 due to Teaming and Boosting in Regicide. 1: 3 Guys worked together to let one guy kill the others and I had still nearly won. 2: BS Ninja Teaming, they would hang out in the same spot and try to assassinate you, impossible to dodge with 2 people. I managed more assassinations in the end (I was ranked higher than both of them in leaderboards) but just Ninja on your own. 3: Guys who would camp or run around with Shotguns, just don't.