Jerks are composed of a central white metal base, a red and white metal core floating above the base, a red eye above that shielded by many pieces of white metal, and two arms that oscillate rapidly, striking the ground and creating shockwaves.
Jerks attack by oscillating their arms rapidly, repeatedly striking the ground and creating short-range shockwaves. They continually move towards Red, as damage is only dealt while in close contact. Jerks also have the most health to make up for their somewhat lacking mobility and range. Upgraded versions of Jerks are capable of pulling Red towards them once in a while, giving them an opportunity to attack.