Leg Breaker is used by hitting the crouch button while running to initiate a slide, then pressing the kick button during the slide to execute the move. It does exactly what it says on the tin - it breaks the legs of any regular shambler or viral zombie hit. Care should be taken around any injured shamblers, as they can blend in with the dead resulting in a nasty surprise if the player tries to loot them before finishing them off. Virals are killed in one hit by this move. Larger zombies don't appear to be affected, though they may take regular kick damage from the move.