He was the Music and Sound Director for the video game developer 3D Realms from 1994 through 2002. He is most well known for his work on Duke Nukem 3D and Rise of the Triad, specifically for creating Duke Nukem 3D's main theme titled "Grabbag". He collaborated with Robert Prince to create the two games' instrumental background tracks. Jackson created all of the tracks for the fourth episode of Duke Nukem 3D, better known as the "Plutonium Pak Add-On" or as the full four-episode "Atomic Edition."[1] In 2016, a remake and remaster called Duke Nukem 3D: 20th Anniversary World Tour was released, containing a new fifth episode by the original level designers, and containing new original music by Lee Jackson.