At the heart of the milky way lies the Bovinion system, ruled by a semi intelligent cow-like species. Although technologically advanced to an acceptable level, these Bovinions have maintained a tribal form of society for several thousands of years. Until recent years, an age-old custom in this society was to scare young Bovinian calves with boogeyman stories about a scary cowboy. Naughty Bovinion calves would, as the story went, be caught by this cowboy's unrelenting lasso.
Recently, a wealthy Bovinian visionary opened up a park where visitors would come to see a genetically re-engineered cowboy in action. But disaster struck and the cowboy escaped his cage. Before the Bovinions could react the cowboy had wrangled the entire park staff. Terror shook the Bovinion civilization as the cowboy started to wrangle every single Bovinion on the planet! Suddenly the Bovinions found themselves out of their cities and wrangled into herds on green meadows by the whisky drinking, bucket spitting, yeeehaawing horror.
Once the entire Bovinian civilization had been wrangled, the cowboy, naming himself Sherriff Lonestar, rode a rocketship into the sunset, his job complete. Now Sherriff Lonestar fights as a mercenary in the robot wars, combining his awesome cowboy-powers with high tech weaponry to earn some solar to spend on whisky and cigars.