This is primarily an escort Mission. After saving the Bar Bot from being harassed by some goons, you'll be tasked to return him to the bar safely. How this mission works is that in certain sections of the level, you'll get ambushed by a bunch of enemies that you'll have to kill in order to advance. (http://www.gamezone.com/originals/2013/01/08/anarchy-reigns-video-walkthrough-free-mission-a-chaser-s-work)