n U.C. 0088, Mashymre was assigned as the Captain of the Neo Zeon Endra-class vessel, the Endra, and was always seen wearing a garnished rose that Haman Karn gave to him, due to his obsession with Haman. He was an optimistic young officer and finds himself in a few comical situations among his own crew. However, after a series of defeats at the hands of Judau Ashta and the AEUG, control of the Endra was handed over to Chara Soon.

During Neo Zeon's invasion of Earth, Mashymre was responsible for the Dublin Colony Drop. Although still dedicated to Haman, by this point he had largely abandoned his pacifistic and idealistic concepts, and has adapted a colder, more destitute outlook towards battle. He fought for Haman at the Battle of Axis against the rebel forces of Glemy Toto. Mashymre was killed after displaying an impressive amount of Newtype powers and detonating his mobile suit while fighting Rakan Dahkaran and his Döven Wolf team. Many were impressed by this display of power, including Mashymre's beloved leader Haman Karn. Despite this, Haman coldly comments that all it really means is that the number of resources available to her had decreased by one.