Operation Gear Grinder

Operation Gear Grinder is an expert difficulty tour for Mann vs Machine, added on October 9, 2012. It consists of three missions across three different maps. Operation Gear Grinder is the only tour of expert difficulty, and thus considered to be the hardest tour of Mann Up mode.

Decoy

 * Desperation

Coal Town

 * Cataclysm

Mannworks

 * Mannslaughter

Rewards
Completing a mission in Operation Gear Grinder will reward the player with a random weapon, robot cosmetic, or item. Completing all six missions in the tour will reward the player with a Carbonado or Diamond Botkiller Weapon (alongside the standard random drop).

Upon completing your first mission in Operation Gear Grinder, you will be given the Operation Gear Grinder Badge. The badge will track your current tour progress, and will gain a level each time you complete a Operation Gear Grinder tour.