The Guardian Units of Nations, often abbreviated as GUN or G.U.N., is a group in the Sonic the Hedgehog series. It is a worldwide military and law enforcement organization. Run by a man only known as the Commander, G.U.N. seeks to protect the earth from all sorts of threats, including Dr. Eggman and the Black Arms.
G.U.N. has vast resources, including an army of soldiers and peacekeepers, fighter planes and other instruments of warfare. While G.U.N. receives orders from the President of the United Federation, it operates under the sole discretion of the Commander, who has been known to use G.U.N.'s resources to bring down enemies.
Song Adventure 2
In Sonic Adventure 2, the GUN organization was introduced. As the plot is revealed, it is shown that GUN were responsible for the mistaken capture of Sonic the Hedgehog, the ending of Project Shadow, the invasion and subsequent deactivation of the Space Colony ARK, and the death of its inhabitants - including Maria Robotnik. GUN's role in this game is simply to contain the threat posed by Shadow the Hedgehog and Dr. Eggman. They send in a government spy, Rouge the Bat, to spy on Dr. Eggman and Shadow, and to retrieve information on Project Shadow via the Ark's database. However, they also attack Sonic and his friends (although, many factors, such as GUN's mistaking of Sonic for Shadow, and Tails' attack on Prison Island, might have provoked this). This proved them to be have caused more harm than good in general, although unintentional. In Rouge's first level, GUN is seen holding a turtle at gunpoint for unknown reasons. The organization was never specifically called "GUN" by the characters, who instead referred to them as "the government" or "the military". The word "GUN" is instead just seen on G.U.N.'s technology and boxes that are spread around the game.
Shadow the Hedgehog
The role of GUN in Shadow the Hedgehog's plot is to repel the invasion of earth by the forces of the Black Arms by any means necessary - including the (presumably unwanted) assistance from Sonic and his friends. During the opening FMV sequence, it is shown that earth is being overrun, with G.U.N.'s forces almost helpless - hence the temporary alliance. It is also strongly hinted during the game and FMV sequences that G.U.N.'s mission is the investigation (and possible destruction) of Shadow himself, depending on the player's moral choices within the game. Their attempts at doing this are caused by the Commander of G.U.N. due to his personal hatred of Shadow, although in two endings he realizes Shadow isn't evil and it was simply a misunderstanding.
G.U.N.'s role in Sonic Adventure 2 was also expanded in Shadow the Hedgehog, where one of the levels takes Shadow and Maria through the colony during the GUN incursion and it also shows Shadow fighting one of their weapons after they try to harm Maria.
If you attack and empty the health bar of a G.U.N soldier while with a hero character, leaving them badly injured, the hero character will tell Shadow to stop it.
Huge Crisis Zone in Sonic Rush is a stage centered on infiltrating several of the organization's battleships at sea. The enemies look similar to G.U.N. Hunter and Hawk robots, and they do not release animals or Chaos Drives when defeated. It is unknown why they attacked Sonic and Blaze, but the name of the stage implies that, either through their unnecessary intervening with the events of the story, or by Dr. Eggman and Eggman Nega taking over the G.U.N. Battleships and control of its G.U.N. robots, that further delay on the situation could have blown up into a more grave scenario.
Sonic the Hedgehog (2006)
G.U.N. has a small role in Sonic the Hedgehog (2006). Shadow has now become an agent of G.U.N., whom they requisition to find Rouge the Bat as she has presumably been kidnapped by Eggman and being held at his base in White Acropolis. After Rouge is rescued and the Scepter of Darkness is retrieved, G.U.N. appears even less. At this point, they are occasionally contacted by Shadow and Rouge for various purposes and for Town Missions.
mong the 150 collectible cards in Sonic Rivals, seven are G.U.N.-related pictures. These cards are "The Commander", "Big Foot", "Flying Dog", "Hot Shot", "Gun Wing", "Hornet-6" and "Shield Hunter"
Sonic Chronicles the Dark Brotherhood
G.U.N. is involved during the events of Sonic Chronicles: The Dark Brotherhood to help Sonic and friends find Knuckles. They are first seen helping in destroying the Egg Carrier. They appear later fighting off the Nocturnus Clan and have a headquarters in Central City as well as taking patrol in Mystic Ruins. They are investigating Knuckles' disappearance and hired Team Chaotix to learn more about the Marauders. Just before Sonic and friends traveled to the Twilight Cage, they gave Rouge instructions to gather any Marauder technology for the scientists to research and possibly re-engineer.
As City Escape reappears in console/PC version of Sonic Generations, many different G.U.N. robots, and also the G.U.N. truck chase scene, re-appears for both Modern and Classic perspectives. For Classic Sonic, the truck's abilities remains unchanged from Sonic Adventure 2, but for Modern Sonic, the truck received several upgrades such as controllable saw-blades and rocket boosters for flight.
As Radical Highway reappears in the 3DS version of the game, many different G.U.N. robots, and the Blue Eagles re-appears for both Modern and Classic perspectives.
Pre-Super Genesis Wave
Post-Super Genesis Wave