Renegade Ops
15 Achievements
8-10h
PS3
A Mess of Stiff Staff Sergeants
Kill Inferno's Sergeants in single player
22.4%
How to unlock the A Mess of Stiff Staff Sergeants achievement in Renegade Ops - Definitive Guide
Parnic
TrueAchievements
TrueAchievements
This is earnable on level 2 in single player and can be achieved on Casual difficulty. After the first few primary objectives (shortly after picking up the key), you'll get a secondary objective to kill all of the sergeants. Simply head toward the gray arrow and destroy any vehicle it points at. There is a time limit on the primary objective while you're doing this and if you complete the primary objective, the secondary objective will go away so make sure you get the sergeants first.
TigerLust, Crowquilt
You can accomplish this while playing Mission#2. At some point, you will receive a secondary objective to kill the staff sergeants.
This one is easy to do at the same time as the primary objective! Bring up the mini-map by pressing 
and you will see gray dots showing the locations of the staff sergeants. Drive over to them and kill them before you destroy the nearby primary objectives.
Imadori
stratege.ru
stratege.ru
This guide was translated automatically.
This action should be performed in the 2nd mission. After you complete several main goals, gray arrows will appear. Just ride them and destroy everyone who is marked by them. Until you destroy all the sergeants, do not take on the next main goal! Otherwise, you will not be able to complete the achievement because all the gray streaks will disappear. Best done on easy or medium difficulty.