Ok, I've posted on this subject all over the place. I've also been killed by the Guardians on countless occasions. So, the deal is when player1 kills player2 (arbitrary name assignments) after player1 has been killed by another player, his kill goes to the guardians. This happens mostly during two melee attacking players. For example; both players have no sheild and are low on health. They both run at each other and player2 melees player1, killing him. However, there is about a half second after you die that you can still melee, so player1 melees after he dies, killing player2. Player2 will see,"You were killed by the guardians" while player1 will see nothing. If you want to see this in action, set up a game with no sheilds, 50% health and do melee attacks only on a small level (Wizard or Prisoner works well).