 Combating the Titans is the military , which is divided into three branches . Foremost in the story is the Survey Corps ( <unk> , <unk> <unk> ) , which goes out into Titan territory to try to reclaim the land . The Survey Corps are heavily derided in society because of their high casualty rate and little sense of progress . The second and largest branch is the Garrison Regiment ( <unk> , <unk> <unk> ) , which guards the walls and the civilian populace . The third branch is the Military Police Brigade ( <unk> , <unk> ) , who guards the royal family and live relatively relaxed lives , although this eventually results in fraud , corruption , and political subterfuge . The soldiers use a tethering system called Vertical Maneuvering Equipment ( <unk> , <unk> Kidō <unk> ) acting as a grappling system , allowing them to jump onto ( and swing from ) walls , trees , or nearby buildings to attack Titans . However , despite it being the soldiers ' primary line of defense against the Titans , it is useless in open and flat terrain like fields . 
