The weaponry available in Duke Nukem Forever ranges from realistic (though slightly futuristic) to completely alien.
Duke is only able to carry two weapons at a time in Duke Nukem Forever (four in the PC version with the expanded inventory option enabled) unlike in previous games, where you could carry every weapon at once.
Executions (Mighty Foot/Uppercut)
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Duke's Mighty Foot
Buttstroking and Punching
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Duke shotgun buttstroking

Duke's Melee Fists
M1911 Pistol
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Duke's New Gold M1911
The pistol in Duke Nukem Forever is an M1911 automatic with an eight round magazine and a laser sight. There are two variants of the weapon: the normal black pistol carried by EDF soldiers and Pigcops, and one with a gold finish and Duke's symbol on the handle that Duke picks up in the Duke Cave level. If the player keeps the gold pistol through the entire campaign and does not swap it for another weapon, they will earn the "Gunslinger" achievement/trophy. A whole clip from it can take down any regular and weak enemy
Shotgun
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DNF Shotgun
The DNF Shotgun is still pump action like in DN3D, but this time it can only hold up to seven shells before needing to manually reload another seven shells into the weapon. It is best used at close range and can kill in one shot if fired in the chest of an enemy.
Ripper
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The DNF Chaingun
George Broussard officially confirmed the Chaingun's return in a post over at the 3D Realms Forums on August 31st, 2006. That same day he stated that the appearance of the Chaingun is very similar to its Duke Nukem 3D counterpart with the exception of a few small updates to modernize its look. The new Ripper Chaingun contains a 60 round drum magazine that is inserted underneath the weapon when reloaded.
Shrink Ray
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The Shrink Ray.
The Shrink Ray is a weapon that can shrink your enemy, allowing you to then stomp on them with Duke's Mighty Foot.
Freeze Ray
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The Freezethrower As It Appears In DNF
When asked if the Freezethrower would be returning (along with the Shrink Ray) George said: "We're bringing them both back. They were too fun, and part of what made Duke 3D unique." (January 27th, 2005.)
The Freeze Ray in DNF fires in a constant beam of freezing energy, and recharges over time. The player will have the option to turn on the "DN3D Freeze Ray" option when they beat the game, which will make the Freeze Ray fire bouncing projectiles like in the original Duke Nukem 3D.
Pipe Bomb
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The pipe bomb is an explosive thrown by hand that can be triggered by a separate hand-held remote detonator, giving Duke the ability to rig levels with some tasty traps.
In response to a forum suggestion on the implementation of hand grenades as a part of Duke's arsenal, George Broussard simply said: "Pipe Bombs > Nades" (July 9th, 2005).
The next day, July 10th, in the same thread, he elaborated on the implementation of pipebombs, mainly the ability to pick up pipe bombs thrown by other players:
Duke's new pipe bombs
"No, that's gameplay and intentional. If you have pipe bombs in the world, they are just that. A pipe bomb. Another player can indeed pick them up if you aren't quick on the detonator :)"
George also clarified that this did not apply to pipe bombs tossed directly at players: "No, it would bounce off. I'm talking about pipe bombs at rest, just lying in the world. You guys see all the details we have to deal with! :)"
In December 2005, George reconfirmed the use of a quick-key to launch pipe bombs on the fly and revealed an added implementation of a time-delayed detonation: "Easier to just toss out a pipe bomb any time you want, with the dedicated key :)" (December 27th, 2005)
The next day he further expanded on this by saying: "Yeah. What we did was that if you just throw out a Pipe Bomb via the quick key, it goes out and detonates in a few seconds. If you want to throw it out and use the trigger, then you select it using the normal weapons interface.
We assume that if you are throwing a bomb out via the quick key, you really want it to go off, quickly.
So this enables you to toss out a few, quickly, in high stress situations, or throw one out via the weapon selection and be more sneaky about it. (December 28th, 2005)
In the game, Duke can carry four pipe bombs at once.
RPG
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Duke's RPG
Devastator
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AT Laser
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A weak burst firing alien laser. Used as a fallback weapon when other weapons are exhausted. It has a fairly high rate of fire.
AT Captain Laser
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The AT Captain Laser.
A laser-firing minigun. There is a brief windup period when the player first holds down the fire key, but after that it fires a steady stream of laser. If the player stops holding the fire key, he/she must go through the "winding up" animation again. The only weapon not in multiplayer.
Enforcer Gun
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The Enforcer Gun
Railgun (Sniper Rifle)
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The Railgun.
Another new addition to Duke's arsenal is the Railgun Sniper Rifle. This weapon is restricted to 3 shots per magazine, but if the shots are fired accurately they can be devastating. It can also shoot through walls and make enemies heads explode when fired properly.
Trip Mine
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In a checklist response to "proximity mines in multiplayer", George answered in the affirmative (January 19th, 2005). It is unclear if he meant the Laser Tripbomb from Duke Nukem 3D instead, nor whether the Proximity Mines would come in place of them or be an added functionality of them.
The Laser Trip Mine in Duke Nukem 3D is a wall-mounted mine that emits a normal laser beam once placed. The activated tripbomb would then explode in a powerful directional blast if any entity crossed its laser. The Trip Mine in DNF functions the same way.
Duke can only carry up to four trip mines at once in DNF. A trip mine can also be placed on enemies, making them run around until they explode.
Doctor Who Cloned Me DLC
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Expander
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The Enforcer Gun
Impregnader
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Slow firing, and limited range fires balls of green goo that mini splashes on impact. Its the only weapon besides the Freeze Ray & turrets to have unlimited ammo, but unlike them it does not require recharge time.
Muliplayer Only
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- Derringer (Capture the Babe only)
- N00b Tube (Call of Duke only)
- DFG (Inferno only)
- Minigun (2Forts1Bridge only)
- Sticky Bombs (Sandpit only)
References
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http://www.youtube.com/watch?v=VRnv_tFKStQ
http://www.youtube.com/watch?v=5pr3mT2TOo4