Sergeant Willard is the Human commander of an M1A1 Battle Tank squadron and a human hero, at least in the tutorial. His special tank, stronger than others, is called Thumper.
He has one special ability, Saturate Area. When Saturate Area is activated, Thumper spins its firing barel up and rapid-fires many shells into the selected area. The attack is inaccurate but incredibly devastating against any enemy unlucky enough to be in the target area.