From the bowels of planet Sera came the subterranean monsters know as the Locust Horde. Faster, stronger and fiercer than any human enemy they had faced in the past. The Coalition of Ordered Governments was forced to advance their weapon technology to survive. Close quarters combat with a Locust was instant death as standard bayonets could not pierce their tough hide. Thus the chainsaw bayonet was born. When fully revved, it can easily tear through Locust armour, flesh and bone and it has given the Gears a fighting chance at survival.