This achievement requires that you finish first in a multiplayer match with at least 10 TOTAL players in the game. Without boosting, this achievement is downright impossible as the online community is completely dead. Use the Achievement Trading Thread or create/join a Gaming Session on True Achievements. At current demand, there is about one chance per month to earn this during a scheduled True Achievements session. Once the session is set up, the group should play 10 consecutive custom Capture the Flag matches with the Score Limit set to 1. The player going for the achievement should capture the sole flag in the game which will give them first place. Good luck trying for this one. It is the hardest multiplayer achievement simply due to the amount of cooperation that is needed.