The past 2 days I have tried to attack red named people and it gives me the same message, "Players in a team can only attack the Captain of Team or plunderers not part of a team." The first guy "Ichiryuugo, aka the lightning main to the right of the convoying fire main" just plundered that fire main as we walked by and saw it. We waited to attack him after the plunder and it wouldn't let us and kept giving the message until he just ran away. The second guy "Slayer the water main" was just standing by himself in Konoha and got the same message. It doesn't look like he is in a team to me and he has moved around while I've tried to attack so shouldn't be in arena. Guessing it's an exploit, because how could Ichi plunder while being on a team? We used to attack red names as a team before...