Mouse was a Duros agent in the Rebel Alliance.
Eight months after the Battle of Yavin, Mouse, together with Luke Skywalker, Basso, Able, Deena Shan, and several other Rebels, conducted the infiltration of the Kalist VI Imperial base, as a specialist for demolition and sabotage. He was noted for his fine sense of dry humor.
When the mission was coming to its conclusion, Mouse was assigned to plant explosives for a diversion. But while installing them, he was discovered by Imperial troops, who became suspicious of his actions and his voice and ordered him to take off his helmet. Mouse did so, and as the baffled troopers stared at him, he broke through their ranks and ran into the maintenance tunnels. The Imperials quickly found him and gunned him down—but they could not stop him from triggering some of the diversionary explosives; a feat that secured the success of his compatriots' mission.
An action figure was made in 2008 by Hasbro as a part of their Expanded Universe Comics line.