Yes, A Traitor.
Everybody was stunned by this realization, not only humans but also the Red lizardmen, but their mood is exactly opposite to us.
There is a look of unbelievability in our eyes and also shock and rage that we have a traitor among ourselves. In the past seven months, as the mission started to get tougher, I began to get in contact with stronger people, which gave me a more clear idea about the traitors.
Not to forget I have done many missions where we have to nab the traitors, though I have not directly participated it, I've seen them battle and knew how dangerous these people which is why just as I had heard that sentence from the mouth of Grimm Monster, I took out my Totem without hesitation.