Duke Nukem 3D is a first-person shooter developed by 3D Realms and published by FormGen Corporation initially for MS-DOS in 1996. It is the third game in the series (the previous Duke Nukem titles being 2D platformers). It runs on the Build engine, the same that powers Blood, Shadow Warrior, and Redneck Rampage, among others. This title was a huge success at the time, thanks to its well-realized interactive environments, sense of humor, and risqué elements. It parodies and homages popular action movies, with the titular Duke Nukem an over-the-top macho hero in a dystopian Los Angeles in the near future enduring an alien invasion.
It received a number of expansion packs, and was ported to various computers and game consoles. An updated version was released via the Plutonium Pak called the Atomic Edition, featuring a new fourth episode called The Birth. Several authorized add-ons were published by WizardWorks. Numerous mods and total conversions have been made for the game, as well as various source ports following the source code being released in 2003, for example Alien Armageddon via EDuke32.
An updated re-release called Megaton Edition was unveiled in 2013 by General Arcade through Devolver Digital, and controversially later replaced by 20th Anniversary World Tour in 2016 by Nerve Software for Gearbox Software (although it did add an exclusive new episode called Alien World Order from the game's original designers). The Atomic Edition is still available for purchase from ZOOM Platform. After well over a decade of development hell a direct sequel was released in 2011 called Duke Nukem Forever using a heavily modified Unreal engine to less than stellar reviews and moderate sales.