Mulet was still young, but already a very bitter person. He took part in the Penninsular War as a member of Napoleon's army in 1815. Mulet was part of an new unit, which served under Connor MacLeod, who was a major at that time. One night Connor offered to help Mulet in the Game, but Mulet refused. He challenged Connor to a duel.
Mulet used his battle axe, Connor his cutlass. Connor quickly sliced open both of Mulet's arms, who was then unable to maintain his hold on his axe which then fell ton the ground. Then Connor took his head. He later hid the body in the nearby swamp.
Note: Mulet only appeared in the original draft and, therefore, he is not considered a canon character, his appearance did not, however, contradict the events of the movie.