Thundergun

The Thundergun is a weapon featured in the campaign and zombie mode of Call of Duty: Black Ops, and can be found via an easter egg in the campaign mission "Numbers".

The Thundergun is a cannon-shaped weapon that fires directional blasts of incredibly strong wind. It has no Iron Sight. It appears to be able to kill large numbers of zombies with a single shot, sending them flying backwards or up. Those who are not killed by the wind blast are thrown backwards and will remain on the ground for a few seconds before getting back up. The Thundergun holds two rounds in a magazine, and holds twelve reserve rounds. Its Pack-a-Punched form is called the "Zeus Cannon," it has an increased magazine size of 4 and carries 24 reserve rounds. It has increased damage, range and radius, now knocking over and slightly damaging zombies off screen. The Thundergun is most important during the later rounds as it is useful for clearing large groups of zombies in order to reach a downed teammate or make an escape. It is extremely useful when swarmed because it will easily kill a large group of zombies in one shot.

It is often used as a reserve weapon, as it has a low amount of ammunition and a moderately slow reload. It can only be reloaded when the entire magazine is empty, except on PC and Wii, where one can execute a partial reload. Wasting ammo on one zombie is not advised. It is also quite a good weapon for hellhounds as it can easily take them out, though sometimes there are so many hellhounds that it is hard to kill them all with such low ammo capacity. It should really only be used against them when they are only attacking you and there is a fairly large group of them and since the last hellhound will drop an max ammo power-up.

Note that some players use a strategy to hoard zombies together and then blast them away with the Thundergun. This is a very good strategy, but it has one flaw. When you use the Thundergun, you do not get any power ups dropped by zombies. This means no max ammo, Double Points, instant kill, etc. This may not seem like a huge factor, but it becomes quite crucial in higher rounds like Round 50 and beyond.

Finding the Thundergun in Campaign
The Thundergun appears in the level "Numbers" as an easter egg, similar to the Ray Gun on "Little Resistance." The steps and video on how to do it are as follows: The gun found in Numbers comes with two shots in the magazine and 12 shots in reserve. It also gains a full ammunition refill after sliding down the pipe and at the second weapons cache. Because of this it becomes very useful when playing on Veteran. In essence, it works much like an extremely powerful shotgun, throwing and almost always instantly killing anyone caught in its massive spread, often with enough force to tear off limbs. It can also reload halfway through a magazine, unlike in zombies.
 * 1) After the interrogation scene ends there are six big white canisters to the front of the player. (Note they are not the small propane tanks on the ground; they are the big white ones)
 * 2) Shoot all six canisters until smoke comes out. (Note you must shoot the canisters before your attackers do. You might want to flashbang your attackers too)
 * 3) Run past the ladder to a small room connected to where you first start the mission.
 * 4) If done correctly the player will see a black tape sticking out of a cassette player next to the door way.
 * 5) Hold down the action key and the tape will disappear from the cassette player, or the obvious shake in the screen as cue.
 * 6) Continue on until you get to the first of Clarke's weapon caches, behind the fridge after the rooftop jump.
 * 7) Look to the left and you should find a cassette player.
 * 8) When at the cassette player, press the use button and notice the cassette go in.
 * 9) If done correctly, notice the tape goes in and the player makes several tunes, and the screen shakes.
 * 10) The Thundergun will appear on the wall above the cassette player.thumb|right|312px|How to get the thundergun in the level "Numbers".

You can trade it for another weapon, and you will be able to pick it up. But sometimes after trading for another weapon Thundergun can become unusable because of bug.

Nazi zombies
The Thundergun can be obtained in the Mystery Box for 950 points. It shoots a shockwave-like blast that knocks any zombies backwards that survive the original hit. When Pack-A-Punched, it is called a "Zeuscannon" and the current ammo is upgraded to 4 rather than 2, and it's reserved ammo is upgraded to 24, rather than 12. It is an essenstial weapon for later rounds since it can be used for pushing back zombies to escape or cover a teammate reviving another. It is most recomended to make loops around Kino der Toten and turn around after 5 minutes and blast 2 blasts from a Thundergun/Zues Cannon, and if lucky enough have another teamate with the non-upgraded Thundergun aswell.

Video
 Video:Call Of Duty:Black Ops Zombies New Badass Gun(Thunder Gun)|The Thunder Gun in action. Video:Call of Duty Black Ops Kino Der Toten Every Weapon Upgraded! Missing ThunderGun(Chuck Norris Cannon)|The Thundergun pack-a-punched into Zeus Cannon

Trivia

 * This is not a usable gun on "Five", probably because players could easily take out the thief with it.
 * The "Zeus Cannon" is an obvious reference to the Greek god, Zeus, King of the Gods, who was said to hurl thunderbolts from his hands.
 * The Thundergun is also the second gun that has a name of a greek god in the upgraded version with the Olympia upgraded named "Hades".
 * The Thundergun is the only Wonder Weapon, when upgraded, that doesn't keep part of it's name. (e.g. Wunderwaffe DG-3 JZ, Porter's X2 Ray Gun, Winter's Fury)
 * The gun has "Osterezheniye" written on its side, which is the wrong spelling in Russian for "Warning." (which correctly is spelled предострежение)
 * If some zombies are not hit directly with the aerial blast, it is possible to see them get back up slowly.
 * The two red glowing lights on the front of the canister when loaded into the gun indicate how many shots are left in the magazine.
 * Richtofen states that this weapon was invented by Ludvig Maxis, but was deliberately hidden from him. This may be a generalization to the whole of Group 935, but if true this is the third wonder weapon to have an associated character, similar to the Wunderwaffe DG-2 and the Monkey Bomb.
 * Only one person can have the Thundergun at a time. However, if the player who has the Thundergun upgrades it to the Zeus Cannon, the Thundergun is once again possible to obtain from the Mystery Box.
 * In Kino der Toten, when Richtofen gets the Thundergun out of the mystery box he says, "Could it be? The DG-3!" This statement indicates the Thundergun could be the DG-3 and the Wunderwaffe JZ DG-3 is merely named as such, however, since Richtofen is only guessing and the pack-a-punch machine does name weapons accurately (a H.Porter was reported to be working on a better Raygun and the upgraded raygun has his name in it being Porter's X2 Raygun) thus it is more likely that this is not the DG-3 but rather a new weapon entirely.
 * Because of little bug during tactical reload in the mission "Numbers" the magazine seems to just disappear from the gun rather than taking it out.
 * The Thundergun and the Ray Gun are the only Wonder Weapons that can be found in campaign. These are also the only two Wonder Weapons to have an official pick-up icon.
 * In a book by Rudolf Lusar called The German Weapons and Secret Weapons of World War Two and Their Development, a weapon very similar to this one is described. It was said to shatter wooden boards at a range of 200 yards by using jets of compressed air. It was also ready to use at an engagement at a bridge over the Elbe in 1945, but was not actually used.
 * When the black cassette tape is inserted into the second recorder, some sounds from GKNOVA6 play. The song that is played is called Damned
 * Unlike the Ray Gun in "Little Resistance," the Thundergun cannot be picked up more than once for unlimited ammo.
 * The Thundergun deals no friendly fire damage in "Numbers", saving you from accidental civilian kills.
 * The Thundergun has been known to rip body parts off of Russians, in the Campaign, instead of launching them backwards.
 * There is an unusable Thundergun in a metal locker in Five. It is in the same room as the unusable Winter's Howl and Death Machine.
 * Killing zombies with the Thundergun can result in the dead zombies twitching on other people's screens, as if they are still alive.
 * The Thundergun can also be found in the mystery box on the Black Ops version of Nacht der Untoten.
 * The Thundergun is a good use on Kino der Toten when you are on high levels and need to link the Teleporter pads.
 * One of Kennedy's unused quotes states "Maybe this came from the Groom Lake Program". Area 51 is built over Groom Lake suggesting that the Thundergun may be American technology stolen by the Russians.
 * On the Wii and Xbox 360 version, when the Thundergun is being used, the Russians start screaming like zombies.
 * In 'Numbers' whenever you reload you will hear a zombie scream (Confirmed for Xbox 360).
 * The Thundergun could have been created by the Ascension scientists.
 * The 3rd person holding animation does not use the foregrip.
 * The Thundergun is not a guaranteed one-hit-kill. Zombies that are at the very edge of its range can survive the shockwave and stand back up.
 * Ironically, the Thundergun doesn't shoot out thunder, it instead shoots out jets of compressed air pressure.
 * There is a glitch on zombies that if you get downed while reloading the Thundergun and someone revives you, you will get back up with no weapon in your hands and will be allowed to buy a third weapon
 * If the player turns off ragdoll effects, zombies will not fly backwards when shot, just fall as if they were taken out by conventional weapons.
 * Zombies can occasionally survive the hit if the they are caught in the hole of the vortex.
 * In the newest episode of "Inside Xbox", it shows the player getting a Thundergun from the Mystery Box when showing Ascension footage, obviously meaning the Thundergun is returning.
 * There was a CCCP writing which means USSR in English plus the Red Star which shows that the Thundergun was Soviet origin.

Inconsistency
Although Richtofen refers to the Thundergun as possibly being the DG-3, the Pack-a-Punched version of the DG-2 is known as the DG-3 JZ. However, since Richtofen stated the gun was deliberately hidden from him, he may not know what the Thundergun is really called. It also has Russian writing on it, although Group 935 -- the group which made the Thundergun -- was a Nazi organization, although, considering Dr. Steiner and Dragovich worked together in the campaign, it is not without plausibility that the Thundergun was a co-operative project, or that the Russians stole it. This inconsistency may potentially be because the Pack-A-Punched weapons do not have 'official' names in real life, and so the displayed names are 'nicknames' for the weapons given by the characters, or that the names are not canon, this however is also inconsistent as a H. Porter was reported to have been working on a upgraded Ray Gun and after being upgraded in the Pack-a-Punch Machine, the Ray Gun's name was changed into"Porter's X2 Ray Gun", thus indicating some naming canon.