G.U.N.', is a military organization featured in the Sonic the Hedgehog. Its status within the Sonic the Hedgehog canon (aside from its Sonic X incarnation) is that of a worldwide military/emergency law enforcement organization, and its duty is to protect the world. G.U.N.'s forces consist of both human soldiers and a large variety of robots that are just as complicated and powerful as those of Dr. Eggman. The G.U.N. robots are powered by "[Chaos Drives]]", power cores invented by Gerald Robotnik after researching Chaos Emeralds. Foot troops of G.U.N. armed with combat knives or a variety of firearms. They first appeared as common enemies of Shadow the Hedgehog. They mostly wear black and blue, but they also have green, tan, black and brown camouflage clothes for jungle areas, and commonly are armed with pistols, rifles and over-shoulder explosives.