Michael Tannen was a Galahad Arms agent and commanding officer operating in Carta.
Most of Mickey's life is unknown. It is known that Mickey joined the Galahad Arms at one point, and received a high status within it. He is also notoriously bad at poker.
Mickey was present in Dusktown when the Traveller's Tempest crew, along with Hector Zambini, walked into a local bar. Mitch, another man in the bar, invited Ruselt into a game of poker, having known of Ruselt's prior victory against Sigma, presumably thanks to Mickey himself. After several turns, Mickey eventually called that he had a four of a kind consisting of Jack cards. Ruselt, who had a Jack of Spades in his possession, called a bluff. Eventually, Mickey was exposed of lying, only having two Jacks. Angered against the winning Ruselt and respectful Mitch, Mickey tried to shoot Ruselt, had one of his guns, which he had bet on, kicked from his hands, which Ruselt soon took as one of his winnings.
Insulted and peeved at the attack, Mickey goaded Ruselt into a showdown outside, but Mickey soon called upon allies to assist, prompting the Tempest crew, Mitch and Zambini to join in, resulting in a shoot-out. During the skirmish, Angel-Ion cut off Mickey's hand to save his allies from a surprise attack. Eventually, Mickey and what was left of the Galahad agents grouped together to kill off Ruselt, Mitch, Luther and Angel-Ion, who were considerably outgunned. Mickey was soon fatally shot in the back from a surprise attack from Dirge.