The G.U.N. Commander is a fictional character in the Sonic the Hedgehog series, first appearing in Shadow the Hedgehog. The GUN Federation's highest ranking officer, he is described as having a "heart of stone",and has complete confidence and an iron will. He appears in several cutscenes in the game where he is seen ordering his troops against the Black Arms and Shadow. He also controls the Diablon robot, one of the final bosses of the game. It is not seen if he is inside it or controls it remotely, but since he is in the GUN fortress after the Diablon robot is destroyed, it is more probable that he controls it remotely.
The Commander grew up with his family on the Space Colony ARK, and was a good friend of Maria Robotnik, whom he considered a sister. However, he saw Shadow being created by Black Doom and Professor Gerald Robotnik, and his family and Maria were later killed in the GUN military's attack. He harbors a deep personal hatred towards Shadow the Hedgehog, blaming him for their deaths, and sends his forces to destroy him throughout the game. The Commander appears to have heterochromia, as he has one blue and one amber eye. In one ending, he reveals Shadow's creation and attempts to shoot him, but Shadow easily dodges. Shadow informs him that, if this is the truth, he will accept his fate and be killed, but not before he discovers the real truth. Through this, the Commander realizes that Shadow is not evil and regrets ever wanting to kill him.
After Shadow defeats Devil Doom and destroys the Black Comet, the President states how ironic it was that people treated Gerald like he was evil, and he ended up saving them all in the end. The Commander and the President realize they were wrong about Gerald's intentions and that he was truly a good hearted person. They decide they will help create peace for the world in honor of Gerald. In the Expert Mode, it is revealed that the Commander had become a grandfather one week after the events of the game and invited Shadow over as part of his apology to the hedgehog. Presumably, this is when Shadow became a GUN agent.
He appears in Sonic Chronicles: The Dark Brotherhood with a slight change of features. His head shape has changed and his eye color is no longer visible. He only appears once during the game after Rouge the Bat brings Sonic and co. to see him. He informs them that they have been tracking the Marauders for a while and have managed to track down four of their bases with help from Team Chaotix.