Duke Nukem: Manhattan Project is a side-scrolling video game for the PC developed by Sunstorm Interactive and produced by 3D Realms. It forms part of the Duke Nukem series of video games. A port of the game was later released on Xbox Live Arcade on June 23, 2010 by 3D Realms directly.
Duke Nukem must save the day once again. The evil Mech Morphix is using a radioactive slime called G.L.O.P.P. (Gluon Liquid Omega-Phased Plasma) to mutate creatures into deadly monsters, which are then taking over Manhattan Island, New York City. These creatures include alligators, rats, cockroaches and boars. There are also a number of enemies that have not been mutated from anything, such as the Fem-Mech, a sadistic and agile feminine robot that wields a whip.
The game is a side-scroller, but it is set in a 3D environment. This allows the path the player takes through the levels to bend and twist somewhat, although the paths are still fixed. It is not a direct sequel to any game, and is instead a stand-alone spin-off game.
The game shares many similarities with the original Duke Nukem game, such at the fact that that they are both side-scrollers, and both games have a half-robotic mad scientist as the main enemy. In fact, Dr. Proton was originally intended to be the enemy in this game, but was replaced by Mech Morphix to avoid possible continuity problems with official sequels (i.e. Duke Nukem Forever).
The player can perform all the basic movements one would expect to be able to do: run, crouch, jump (and double jump), kick, slide kick, and grab and pull up on ledges. Due to the game being set in a 3D environment, the camera can be moved around a little and zoomed in or out to get a better view of the surroundings. There is a cheat that enables the camera to be moved to any position at all, which is useful for taking screenshots.
The game has 8 chapters, each of which contains 3 parts. In each part, the player must locate and rescue a babe strapped to a G.L.O.P.P. bomb, and locate a keycard to use to unlock the path to the next part.
There are no vehicles in the game, although at some points the player can use a Jetpack to fly over large voids or hazardous ground.
The controls are minimal, with buttons only for jumping, moving sideways, crouching, firing and changing weapons.
The health meter is renamed the EGO meter. EGO acts just like health, in that EGO begins at 100, is lost for being shot, and the level is lost when it reaches 0. There are pick-ups that will increase the player's EGO, and killing an enemy will also boost it. If the EGO is boosted above the maximum, it will slowly decrease until it reaches that maximum.
There are 10 secret items hidden in each part of each chapter. Collecting all 10 Nukes in the same part will permanently increase the player's maximum EGO level by 2.
- Collecting all the Nukes in the game on Easy difficulty will double the strength of the Mighty Boot.
- Collecting all the Nukes in the game on Medium difficulty will halve the damage the player receives, and turns Duke's shirt blue (except for in the end-of-level cutscenes).
- Collecting all the Nukes in the game on Hard difficulty will reward the player with the X-3000, the most powerful weapon in the game.
The game CD includes a level editor named PrismEd, which can be used to create user levels or viewing the original levels in detail and at leisure. However, despite this, there is currently only a small level editing community.
Many of the weapons in the game have featured in one or more previous Duke Nukem games.
- Mighty Boot - Duke's preferred melee attack. Kicking an enemy inflicts significant damage to it, but leaves the player vulnerable to a counter-attack. Killing an enemy by kicking it or landing on it will double the EGO boost that death provides. It is also used for sliding kicks, and for crushing non-mutated creatures.
- Golden Eagle Pistol - The weapon the player starts the game with. It does less damage per shot than the Mighty Boot, but it can hit enemies at a distance.
- Shotgun - A more powerful gun.
- Assault Rifle - Has a high fire rate, and overall is about as damaging as the Shotgun. Keep an eye on your ammo level, though.
- Pipebomb - A grenade-like explosive, straight from Duke Nukem 3D. It has its own special button for throwing quick Pipebombs without having to change weapons. Very useful for blowing things up.
- GLOPP Ray - This weapon does the opposite of G.L.O.P.P., and restores mutated enemies back to their original forms. Once they are regular creatures again, they can easily be crushed underfoot.
- Pneumatic Rocket-Propelled Grenade - Fires explosive rockets. Uses Pipebombs as ammo.
- Pulse Cannon - Fires bolts of electricity, and can be charged up to fire a very destructive ball of lightning. Shares ammo with the GLOPP Ray.
- X-3000 - The secret weapon, unlockable by collecting all the Nukes in Hard difficulty. It's a lightning gun that automatically targets all enemies on the screen. Thunder rumbles in the background just when you're holding it, so you know it's a big deal.
All power-ups activate the moment they are picked up, and last for a limited amount of time.
- Double Damage - Duke glows red and does double damage. Upon picking this power-up up, Duke utters the catchphrase: "It´s clobberin' time!"
- Forcefield - Three green objects rotate around Duke, making him invulnerable. Whenever Duke would be damaged while he is holding this power-up, the forcefield sizzles and glows.
- Jetpack - Allows aerial travel.
Initial release copies of the game came with a bonus metal keychain. This keychain contained the Duke Nukem logo and Statue of liberty on one side, and a NYC subway token imprint on the other side. Subsequent releases of the game lacked the keychain.
The only exterior difference between these two versions of the game was a sticker on the outside of the box saying "All New Duke: Special Edition Keychain Inside!". Later prints still had the "All New Duke" sticker, but without the keychain language. A further version of the box had no sticker at all.