The Mech is a unit in the Nintendo Wars series. The Name is a common abbreviation of mechanized infantry.
The mech is an invaluable addition to any army facing vehicles and short on cash. Able to travel at a rate 2 through any terrain in the Advance Wars series, they can be used to cross difficult terrain to attack enemy weak points. Combined with Sami, the infantry specialist, they can be potent force in a "Mech Flood", a tactic where the player builds primarily mechs to erode their enemy's superior forces.