Field Engineer -- Pioneer
You are a combat engineer in the infantry. You will support infantry units where they require field engineering. This includes demolition of obstacles, bridging, construction of obstacles and fortifications, mining, demining and other tasks.
This is probably the toughest job in the Army, even tougher than being a Commando in some ways. You will be the first man in a assault, carrying bangalore torpedoes or breaching charges to clear a gap for the rest of the unit to assault through. You will move on foot through the jungle with the infantry, but carry much more weight in mines, tools and explosives than the infantrymen you are supporting. You will help build infantry bridges, consisting of 80+ kg sections moved into place by hand. You will clear minefields.
You poor bugger, I salute you.
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Everybody who knows anything about the Army will respect you later, but you will really earn this respect in sweat and blood. Watch out for your toes -- the most common injury to combat engineers is dropping extremely heavy things on their feet. Also watch out for your back -- you will carry a lot of weight. Make friends with your unit, and get them to help you or you will surely die on exercise with the amount of things you must do.