I, Xim Xam, have a brother "Mix Max" who feels all my pain!
— Xim Xam
Xim Xam was the Jeff Winger's reimagining of Ian Duncan. He existed in a "G.I.JOE™" themed reality dreamt up by Jeff when he fell into a coma. Xim Xam had a twin brother named Mix Max with whom he shared a unique bond; whenever one of them experienced pain the other felt it as well. While his brother had a normal civilian life, Xim Xam chose instead to become an international terrorist as a member of COBRA™ . Xim Xam's first appearance was in the Season Five episode "G.I. Jeff". He is voiced by actor/comedian John Oliver.
Xim Xam was one of several COBRA™ operatives stationed at a secret excavation site code-named "Greendale". The buried structure they had uncovered resembled a school and was filled with mysterious artifacts which hinted at another reality. The operation was being run by Vice Cobra Assistant Commander and Xim Xam was sent to protect the site alongside Major Dick and Overkill. Upon learning of their comrade Destro's death on the battlefield, Xim Xam and Major Dick went to talk Vice Cobra Assistant Commander. They were both worried about how they were now able to die in combat and insisted that COBRA™ give them additional hazard pay for their services. Vice Cobra Assistant Commander denied their request and told them that budget wouldn't allow it now that their insurance rate has gone up due to the Destro incident.
Xim Xam and Major Dick demand hazard pay.
Xim Xam pointed out how COBRA™ spent millions of dollars on mechanized weaponry every week yet couldn't afford to give them a raise. The discussion was interrupted by Overkill who informed Vice Cobra Assistant Commander that G.I.JOE™ troops had snuck onto the premises. Xim Xam, Major Dick and Overkill were sent out to deal with the intruders. Xim Xam found them not long after they had already wounded Overkill. He warned them about the psychic link he had with his twin Mix Max; any pain they inflicted on him would also be felt by his brother. In response the G.I.JOE™ team squad leader Wingman shot Xim Xam in the shin. Miles away at a restaurant, Mix Max was waiting a table when he felt the gunshot and fell down from the pain. Back at Greendale, Overkill and Xim Xam hopped away from Wingman's squad on one foot while nursing their shins ("G.I. Jeff").
Xim Xam's appearance and abilities were an homage to the G.I.JOE™ characters Tomax and Xamot. They were the head of COBRA™'s Crimson Guard troopers, a division of soldiers who specialized in infiltration and espionage. As Xim Xam and Mix Max demonstrated, Tomax and Xamot can feel each other's pain.