G.U.N. is a fictional global military organization responsible for maintaining peace and security on Earth. It often serves as a countermeasure to threats posed by villains like Dr. Eggman and other world-threatening forces. Although typically allied with the protagonists, their morally gray actions and history often create tension between them and Sonic's group. They are in charge of Global Peacekeeping on an international scale to prevent large-scale disasters, including threats from alien invasions, rogue robots, and terrorist activities. The organization employs highly advanced weaponry, vehicles, and robots. They rival Dr. Eggman's technology and are among the most technologically advanced entities in the Sonic universe. G.U.N. conducts secretive experiments and projects, such as the Shadow Project, which created Shadow the Hedgehog aboard the Space Colony ARK. They field an army of soldiers, mechs, and aerial units to respond to crises. G.U.N. frequently appears in action-packed scenarios involving battles against Eggman or other antagonists.