Ben K

Ben K is a warrior robot from Mega Man 6. It pulls out a spear-like weapon and spins it, deflecting all frontal shots while doing so. After a few seconds, it throws the spinning blade out and repeats the movement with a new blade. Mega Man can shoot Ben K for a few seconds in between the spinning blades to shoot, although with some clever use of special weapons (such as Knight Crush, used at an angle to get behind the spear, or Silver Tomahawk, used in a way that arcs underneath) Mega Man can even strike Ben K when it spins its spear.

Trivia

 * Ben K was inspired by legendary Japanese warrior-monk Saito Musashibo Benkei (ca. 1155-1189 A.D.). Just like Mega Man, Benkei is known to collect the weapons of his fallen foes.