King Duke was composed by Bobby Prince for the game Duke Nukem II (DOS). The song was composed using Sequencer Plus Gold in MIDI format and then converted to an IMF file to be played on the OPL2 chip. The song is played during the boss battles of each episode.
This song's internal title is "kingduka". The official title, an oxymoron since a duke is not a king, was verified by Bobby Prince.
Listeners have compared the beginning of this song with Raining Blood by Slayer.