Around six weeks after Emergence Day, Carlson was part of the effort to defend the city of Halvo Bay from a huge Locust assault. Carlson helped defend a courthouse along with other members of the Onyx Guard as Col.Ezra Loomis put Kilo Squad on trial inside. As Lt.Damon Baird gave his first round of testimony, Carlson was killed by Locust forces in the Halls of Judgment. Carlson's COG Tag was later recovered by Baird.