Zero Point Energy Field Manipulator

{{Otheruses|Gravity Gun}}
{{Weapon Infobox
| image=FileGravity Gun.jpg|250px
| image2=FileGravity Gun super.jpg|250px
| name= Zero Point Energy Field Manipulator
| affiliation= Resistance
| damage= *Varies depending on the object/Normal
*Instant Kill/Super
| magazine= Infinite
| maxammo= Infinite
| ammotype= Objects/Props
| rate of fire= 
| accuracy= Varies
| range= Short to medium
| maker=Eli Vance
| usedby= *Gordon Freeman
*Alyx Vance
*Wallace Breen (Half-Life 2 storyline 13 Dark Energy|briefly)
| entity=weapon_physcannon

{{Quote|The Zero Point Energy Field Manipulator is not a toy, Alyx!|Judith Mossman|Half-Life 2|Filemo notatoy.ogg}}

The '''Zero Point Energy Field Manipulator''', more commonly known as the '''Gravity Gun''', is a gravity-based device, originally designed for handling hazardous materials, but, as Alyx Vance stated, is now primarily used for heavy lifting. At its core is some sort of gold-colored substance. Introduced to Gordon Freeman by Alyx shortly after his arrival at Black Mesa East during ''Half-Life 2''’s fifth chapter ''Half-Life 2 storyline 5 Black Mesa East|Black Mesa East'', the Gravity Gun soon becomes an invaluable tool in Gordon's arsenal, and is now considered one of his signature weapons.

FileAlyx gravity gun first retrieving.jpg|thumb|200px|left|Alyx introducing the Gravity Gun to Gordon at Black Mesa East.

*The Gravity Gun has two basic modes. The primary fire releases an energy blast, which pushes the targeted object with a tremendous force. This is useful for clearing out barriers, or moving objects that cannot be picked up, such as disabled cars. The secondary fire picks objects up, and holds them just ahead of the device. These objects can then either be dropped by pressing the secondary fire button a second time, or they can be pushed with the primary fire. The secondary fire can only pick up lighter objects, mainly those which Gordon himself can carry, but the primary fire is capable of pushing much larger objects even if the secondary fire cannot affect them. The gun cannot affect most organic material, though there are a few exceptions.

*Using the Gravity Gun's secondary and primary fire modes in conjunction allow it to be used as a powerful weapon. Since it uses physics objects rather than conventional ammunition, there is virtually no limit to how many times it can be fired. However, this advantage is balanced by the need to "reload" after every shot, by grabbing a new object. Depending on the object fired, the Gravity Gun can be one of the most damaging weapons in the game. Heavier objects like metal barrels and propane tanks can even kill Overwatch|an Overwatch soldier with a single blast, but conversely, objects such as plastic crates, plastic bottles or wooden pallets will do very little to no damage due to their weaker materials. Explosive barrels, in particular, are highly devastating when used with the Gravity Gun, but this can backfire if the barrel is shot by an enemy while being held by the gun. The Gravity Gun is most effectively used as a short to mid-range weapon, since the physics objects it uses for ammunition are affected by gravity once they leave the device's hold.

*Ravenholm was built around the use of the Gravity Gun, as it contains most physics elements seen during the series. Indeed, one of its early names is "Phystown".

*The Gravity Gun is also handy for moving trapped vehicles, such as the Scout Car, as well as the Muscle Car. This is particularly efficient for flipping the Scout Car, if it flips over onto its roof.

*In addition to its use as a weapon, the secondary fire of the gun can be used to pull objects over from a distance, allowing Gordon to access supplies or other objects, that are out of reach or behind a Force Field. 

*It can also be used as an alternative to the crowbar, in order to smash supply crates open (by picking them up and pushing them into the floor), which is faster than using the crowbar, and becomes mandatory during the first half of ''Episode One'', during which Gordon is without his crowbar, until Barney Calhoun gives him a new one in the game's fourth chapter, Half-Life 2 Episode One storyline 4 Urban Flight|Urban Flight.

*Another useful strategy is throwing back a Fragmentation Grenade (Half-Life 2)|Fragmentation Grenade to its sender. This can be dangerous, however, as the grenade can detonate while the player is holding it.

*The Gravity Gun can also be used to grab larger objects, such as metallic plates or radiators, and holding them up as makeshift shields. This was demonstrated by Valve in the E3 2003 demonstration ''Traptown''. 

*Larger objects, such as disabled cars, or even some pieces of furniture can only be pushed using the primary fire. Cars can kill several enemies at once and are also useful in ''Episode One'', when Freeman must block several Antlion holes with them.

*It should be noted that the secondary fire of the Gravity Gun does not automatically tractor in targeted objects. The object must be brought within a certain distance for the field to directly capture it, during which time it is still subject to gravity. The gun must also be constantly trained on the object to maintain the effect, until it has been captured.

*In addition to its primary uses, the Gravity Gun can be used in more esoteric ways. Manhacks, City Scanners and Shield Scanners can all be held and punted by the gun; the first, in particular, can be held by the gun for use as a makeshift chainsaw. All three are heavy enough to deal significant damage if pushed, and will be destroyed if pushed into a nearby wall. However, if pushed over greater distances, they will stabilize their flight. It can also be used to grab and recalibrate Hopper Mines, or removing Rollermines from vehicles. A Rollermine grabbed in such a manner can be reprogrammed by Alyx to attack hostile targets instead of friendlies, and can also be pushed into enemies directly. Combine Sentry Guns can also be manipulated by the gun (disabled by being thrown when being enemies, replaced after being knocked down when being friendly).

*Though the gun cannot affect most organic matter, Headcrabs and Antlions are vulnerable to the primary fire. Three blasts from the primary fire will kill any Headcrab. Antlions are harder to kill in this manner, but being hit by the gun causes them to flip over, exposing their weaker undersides.

*The Gravity Gun appears to be quite heavy, as Alyx Vance and other characters that attempt to use the gun have some trouble lifting it. It also has significant recoil, as demonstrated when Alyx uses it to push a train door away. However, Gordon Freeman's HEV Suit presumably allows him to use the device with ease.

*Judith Mossman takes the Gravity Gun very seriously, and advises Alyx to do the same in her infamous sentence "''The Zero Point Energy Field Manipulator is not a toy, Alyx!''". 

*The tutorial for using the Gravity Gun takes place in Black Mesa East's outdoor scrapyard, in which Alyx teaches Gordon the basic actions and uses of the device, notably by playing fetch with Dog and his own reprogrammed Rollermine, until they are interrupted by a Combine attack, forcing Gordon and Alyx to separate.

===Common objects===

Most common objects found in the environment that can be picked up by the Gravity Gun and thrown at enemies, among others. Non-exhaustive list.

Includes "random" items found in the environment. Some items are very light and thus useless for gameplay. Some are heavier and can be used against opponents.

FileCinderblock.jpg|Cinderblock, for instance used in a puzzle early in the Canals.
FileFlavia can.jpg|"Flavia" paint can. Does little damage but paints the target white, including walls.
FileWatermelon.jpg|Watermelon. Has no actual purpose.
FileSawblade.jpg|Sawblade, mostly used in Ravenholm. Quite damaging, and is capable of dismembering Zombies
FileRed couch.jpg|Red couch (can only be pushed, not picked up).
FileNp toilet.jpg|Toilet bowl model.
FileCanister 01.jpg|Blue canister. Doesn't explode.
FileCanister 02.jpg|Red canister. Doesn't explode
FilePropane canister.jpg|Propane canister. Doesn't explode.
FileGas can blue.jpg|Blue gas can. Doesn't explode.


Environmental explosives that can also be detonated with bullets, and may backfire when shot at by enemies.

FileExplosive barrel.jpg|Explosive barrel, commonly found in the series.
FileGas can red.jpg|Red gas can.
FilePropane tank.jpg|Propane tank.
FileExplosive butane can 01.jpg|Butane can.
FileExplosive butane can 02.jpg|Ditto.

====Useful items====

Also includes every single weapon and ammunition.
All health/armor pickups are based on the 100 point limit.

FileSupply crate.jpg|Supply crate. Can be destroyed faster than with the crowbar.
FileMedkit.jpg|Medkit. Instantly heals upon player contact.
FileHealth vial.jpg|Health vial. Instantly heals upon player contact.
FileHEV battery.jpg|HEV Suit battery. Instantly grants armor upon player contact.
FileEmergency flare ep1.jpg|Emergency flare, introduced in ''Episode One''. Lights up when picked up. Can be thrown and picked up again until it consumes itself.
FileCar battery.jpg|Car battery, used in a puzzle along the Coast.

==Dark Energy-powered Gravity Gun==

*When exposed to the Confiscation Field in the Citadel, the Gravity Gun is "supercharged", rather than being vaporized as Gordon's other weapons are. It also cripples the field itself in the process. Once supercharged, the Gravity Gun emits blue light rather than orange, quakes in Gordon's hands, and creates small bolts of energy across its muzzle. Its powers are vastly enhanced, enabling it to manipulate objects of far greater mass than it could normally (such as Combine interfaces), as well as pull and repel them with greater force. 

*Its most significant enhancement, however, is its ability to manipulate living, organic matter. Any Overwatch unit pushed by its primary fire is instantly killed, and their body retains an energetic charge, that will kill others if it strikes them. If grabbed by the gun's secondary fire, they are likewise killed instantly. 

*It also has the side effect of vaporizing any weapon the soldiers are carrying. Interestingly, this also occurs when Alyx Vance|Alyx kills an enemy herself, using her handgun. 

*Energy Balls can also be picked up and sent flying towards enemies, similar to the OSIPR's secondary firing mode.

*The first time the Gravity Gun is supercharged is in ''Half-Life 2''’s thirteenth chapter, ''Our Benefactors'', when Gordon's Prisoner Pod deposits him into a Confiscation Field; it remains supercharged until the end of the game. During this time, Gordon's HEV Suit also becomes 'supercharged' to the point of harboring 200% energy, and Combine energy chargers can even restore Gordon's health as well. 

*At the start of ''Half-Life 2 Episode One|Episode One'', it is no longer supercharged, but becomes supercharged again after Gordon and Alyx re-enter the Citadel to stabilize the Citadel Core|core, when Gordon accidentally enters another Confiscation Field. It remains supercharged until Gordon reactivates the core's containment field, at which point the Gravity Gun reverts to its normal state, presumably due to a significant dark energy drain effect.

==Related Achievements==
{|class=wikitable style="vertical-aligncenter;" width=50%
!colspan="2" style="text-alignleft"|The Orange Box Achievements Half-Life 2 game|Any ''Half-Life 2'' game
|rowspan=2 width=64px|FileHlx kill enemies withphysics.png
!style="text-alignleft"|Bone Breaker (5G)
|''Kill 30 enemies with thrown physics objects.''
|rowspan=2 |FileHlx kill enemy withhoppermine.png
!style="text-alignleft"|Deadly Harvest (5G)
|''Kill an enemy by planting a Hopper Mine.''
|rowspan=2 |FileHlx kill enemies withmanhack.png
!style="text-alignleft"|Hack Attack! (5G)
|''Kill five enemies with a Manhack.''
|rowspan=2 |FileHlx kill soldier withhisgrenade.png
!style="text-alignleft"|Hot Potat0wned (10G)
|''Kill a Combine soldier with his own grenade.''
|rowspan=2 |FileHlx kill enemies withoneenergyball.png
!style="text-alignleft"|Conservationist (5G)
|''Kill five enemies with the same Energy Ball.''
|rowspan=2 width=64px|FileHlx kill elitesoldier withhisenergyball.png
!style="text-alignleft"|Think Fast! (10G)
|''Kill an Overwatch Elite|Elite Soldier with his own Energy Ball.''
!colspan="2" style="text-alignleft"|''The Orange Box Achievements 2|Half-Life 2''
|rowspan=2 width=64px|FileHl2 get gravitygun.png
!style="text-alignleft"|Zero-Point Energy (5G)
|''Get the Gravity Gun in Black Mesa East.''
|rowspan=2 width=64px|FileHl2 makeabasket.png
!style="text-alignleft"|Two Points (2G)
|''Use Dog's ball to make a basket in the scrapyard.''
|rowspan=2 width=64px|FileHl2 beat ravenholm noweapons.png
!style="text-alignleft"|Zombie Chopper (25G)
|''Play through Ravenholm using only the Gravity Gun.''
|rowspan=2 width=64px|FileHl2 kill enemy withtoilet.png
!style="text-alignleft"|Flushed (5G)
|''Kill an enemy with a toilet.''
|rowspan=2 width=64px|FileHl2 disintegrate soldiersinfield.png
!style="text-alignleft"|Atomizer (10G)
|''Disintegrate 15 soldiers by throwing them into a Combine ball field.''
!colspan="2" style="text-alignleft"|''The Orange Box Achievements 2 Episode One|Half-Life 2 Episode One''
|rowspan=2 width=64px|FileGrave Robber.jpg
!style="text-alignleft"|Grave Robber (5G)
|''Steal a Zombine's grenade.''
|rowspan=2 width=64px|FileZombie-que.jpg
!style="text-alignleft"|Zombie-que (5G)
|''Use flares to light 15 Zombies on fire.''
|rowspan=2 width=64px|FileCar Crusher.jpg
!style="text-alignleft"|Car Crusher (5G)
|''Use the cars to squash 15 Antlions in Episode One.''
|rowspan=2 width=64px|FileThe One Free Bullet.jpg
!style="text-alignleft"|The One Free Bullet (40G)
|''Finish the game firing exactly one bullet. Grenade, crowbar, rocket, and Gravity Gun kills are okay!''
!colspan="2" style="text-alignleft"|''The Orange Box Achievements 2 Episode Two|Half-Life 2 Episode Two''
|rowspan=2 width=64px|FileGrave Robber.jpg
!style="text-alignleft"|Grave Robber (5G)
|''Steal a Zombine's grenade.''
|rowspan=2 width=64px|FileEp2 kill chopper nomisses.png
!style="text-alignleft"|Puttin' On a Clinic (15G)
|''Defeat the chopper in Episode Two without any misses.''
|rowspan=2 width=64px|FileEp2 kill hunter withflechettes.png
!style="text-alignleft"|Payback (10G)
|''Kill a Hunter with its own flechettes.''

==Behind the scenes==
*During ''Half-Life 2''’s development, the Gravity Gun had several names, including "Zero-Point Gun"Development of Half-Life 2 game|''Half-Life 2'' leak or "prototype physics manipulator".''Half-Life 2 Raising the Bar'' Another weapon, the Physgun, whose model resembles the final Gravity Gun model, is present in the Development of Half-Life 2 game|''Half-Life 2'' leak and was used as a gameplay prototype for physics manipulation and to demonstrate the physics simulation capabilities of Source at E3 2003.

*As heard in sound files featured in the ''Half-Life 2'' leak files, Eli was to explain to Gordon at Black Mesa East, that while Black Mesa was a "decade away from harnessing the zero-point energy field", it turned out that the Combine had already pioneered this technology. He then explains that the Gravity Gun is based off "a little piece of tech Alyx liberated on one of her expeditions". He also calls the Gravity Gun's secondary fire mode "asymmetric". The Gravity Gun's "grand daddy" was used to manipulate hazardous materials in the Combine's portal reactors, suggesting the Gravity Gun uses Combine technology.Development of Half-Life 2 game|''Half-Life 2'' leak files

*At some point during ''Half-Life 2''’s development, Ravenholm was set at the end of the Canals, and preceded Black Mesa East. Consequently, it didn't include the Gravity Gun, and as such, its gameplay only focused on Father Grigori's intricate traps (hence the name being used at that time, "Traptown").WC mappack

*The Gravity Gun bears a vague resemblance to the Anti-Mass Spectrometer from ''Half-Life'', notably the prongs. The Aperture Science Handheld Portal Device from the ''Portal'' series has some similarities as well; it was actually originally based on the design of the Gravity Gun, as seen in early ''Portal'' screenshots. It retained the prongs in the final design, as well as an zero-point energy field manipulator, allowing it to pick up small objects, but not throw them.''The Orange Box Prima Guide'' The Gravity Gun can also be seen in the Aperture Science Enrichment Center|Enrichment Center lab where Doug Rattmann and Henry are working prior to GLaDOS killing its inhabitants, in the comic ''Portal 2 Lab Rat''. Interestingly, in that same comic panel, we can also see two Black Mesa health and energy chargers, as well as what seems to be a Combine health charger. Whether these appearances were meant to be mere easter eggs, or perhaps have some meaningful relevance to the series' narrative remains to be seen.

*When the player dies using the supercharged Gravity Gun, it disintegrates.

*In ''Episode One'', during the sequence where the supercharged Gravity Gun is used, enemies killed by Alyx will still lose their weapons as if hit by the Gravity Gun. This is likely a small oversight, as the purpose of the Gravity Gun destroying enemy weapons is also to prevent the player from taking them during the sequence.

*The film ''WikipediaDistrict 9|District 9'' features an alien weapon influenced by the Gravity Gun, built into a powered armor suit. It is able to pick up almost anything, including a pig, and hurl it with incredible force. It appears to have a much stronger field since it is also able to halt bullets and in fact keep them in an area just ahead of the muzzle, somewhat similar to a zero point energy field.



File03 Vance+Vance-2.png|Concept art for the early "prototype physics manipulator" being held by Eli Maxwell.
FileAperture Science Gravity Gun.png|The Gravity Gun in ''Portal 2 Lab Rat''.

===HUD icons===

FileGrav gun hud icon.svg|HUD icon, from "HalfLife2.ttf".
FileGrav gun pickup.svg|HUD pickup icon, from "HalfLife2.ttf".
FileObject pickup.svg|Unused HUD pickup icon used for when a player picks up an object with the Gravity Gun in ''Half-Life 2 Deathmatch'', from "HalfLife2.ttf".
FileObject throw dead.svg|HUD icon used for when a player is killed by an object thrown with the Gravity Gun in ''Half-Life 2 Deathmatch'', from "HL2MP.ttf.


FilePhysgun view.jpg|Physgun viewmodel.
FileGravity Gun.jpg|Worldmodel.
FileGravgun viewmodel.jpg|Viewmodel.
FileGravity Gun super.jpg|Supercharged worldmodel.
FileGravgun super viewmodel.jpg|Supercharged viewmodel.


FileGravity gun first stored.jpg|The Gravity Gun stored in its cupboard at Black Mesa East.
FileAlyx gravity gun first buttons.jpg|Alyx opening the Gravity Gun's cupboard.
FileAlyx gravity gun first waiting.jpg|Alyx waiting for Gordon to take the Gravity Gun.
FileD3 citadel 030116.JPG|The Gravity Gun being transformed in the Confiscation Field.
FileD3 citadel 030166.JPG|Killing Combine soldiers with the transformed Gravity Gun.
FileDarkenergy.jpg|Holding an Energy Ball in front of Combine soldiers with the transformed Gravity Gun.
FileD3 breen 010009.jpg|The Gravity Gun being taken away by an Overwatch Elite before Breen's office.
FileD3 breen 010000.jpg|The Gravity Gun being held by the Overwatch Elite.
FileD3 breen 0100225.JPG|Wallace Breen talking to an Advisor with the Gravity Gun on the floor.
FileStrider Buster held.jpg|Magnusson Device being held by the Gravity Gun.

==List of appearances==
{{Imagecat|Zero Point Energy Field Manipulator images}}

*https// ''Half-Life 2'' at E3 2003 Traptown {{1st}} {{Nc}}
*''Half-Life 2''
*''Half-Life 2 Deathmatch'' {{Nc}}
*''Half-Life 2 Raising the Bar'' {{C|As "prototype physics manipulator"}}
*''Half-Life 2 Lost Coast'' {{Nc}}
*''Half-Life 2 Episode One''
*Source Particle Benchmark {{Gf}} {{Nc}}
*''Half-Life 2 Episode Two''
*''Portal 2 Lab Rat''
*''The Final Hours of Portal 2''


CategoryHalf-Life 2
CategoryResistance weapons
CategoryGravity manipulators
CategoryExperimental weapons