Super Mutant Behemoth

Super Mutant Behemoths are giant Super Mutants living in the ruins of Washington, DC. There are five in total, and they do not respawn after you kill them. On the PS3, Xbox 360 and Windows versions of the game, there is an achievement entitled "The Bigger They Are..." obtained by destroying all five. It is unknown how these particular mutants achieve this size, but if their numbers are any indication, it rarely happens. For that, the Wasteland can be thankful.

Locations
Video locations of all Super Mutant Behemoths

GNR: YouTube video for Behemoth at GNR:
 * The Behemoth right outside the entrance to the GNR Building is the easiest to find and is actually impossible to miss if you attempt Galaxy News Radio (quest). You will have ten Brotherhood of Steel members to back you up, though they are not invincible and most will likely be killed quickly. One of the Brotherhood members is in possession of a Fat Man weapon and will die quickly, before having a chance to use it. The lamppost in the area is fragile-looking, but the Behemoth considers it a wall, and it can serve as effective cover from the Behemoth. If you have trouble defeating this behemoth it’s possible just to run to door of the GNR building. There is a back exit to this building so you will not have to face him on the way out. Also when you quick travel back to this location you will be placed behind the sandbags pretty much out of harms way near the door. Another possible strategy is to take cover under the GNR building, coming out when your AP recharges to use VATS.
 * http://www.youtube.com/watch?v=rTZVrHEneG4

Evergreen Mills: YouTube video for Behemoth at Evergreen Mills:
 * In Evergreen Mills, the Raider-controlled train yard, a behemoth is trapped by an electric fence. When approaching the area from the south, the generator can be easily destroyed with any rifle; a melee will ensue in which most of the raiders will die killing the behemoth. However, no experience will be gained by this method. The easiest method of legitimately defeating the behemoth is to clear the area of raiders, lay several Bottle Cap Mines near the gate(but far enough away from the generator so they don't detonate when it explodes) and then release the locks on the cage. Alternatively, the Behemoth can be attacked by ranged weapons through the mesh gate while the generator is still active. The roof of the nearby train car offers a clear view of him.  However, it is possible that the Behemoth may escape during the player's shootout with the Raiders, forcing the player to deal with him in the tight confines of the camp.  Another alternative is to jump between the carriages to get to the other side of the carriages.  The behemoth will try to get through but can't and eventually will run off.  Just jump back over and it comes back, repeat until the Behemoth dies. Normally the Behemoth won't attack any followers with this method.
 * http://www.youtube.com/watch?v=TbW4VJajdmE

Capitol Building:
 * A Behemoth can be found in the Capitol Building fighting Talon Company mercenaries at the west entrance. There is a considerable amount of fighting between Super Mutants and Talon Company so its best to just sit back and watch (or snipe if you want the experience points). After a bit you'll find the room under the dome and that is where the Behemoth is waiting.  He should be getting shot at by more Talon Company so just wait until he has low health and hit him with one nuke.

Takoma Park: YouTube video for Behemoth at Takoma Park:
 * A Behemoth is located southwest of the Takoma Industrial in Takoma Park. There is a truck near a water tower a few feet away. On the truck you can see a dead mercenary and a switch that activates some artillery that makes the fight a lot easier.
 * http://www.youtube.com/watch?v=8WrjFAgC6Lc

Jury Street Metro Station: YouTube video for Behemoth at Jury Street Metro Station:
 * One final Behemoth is located at a Super Mutant camp, after following a series of search party notes (Unmarked quest: Searching for Cheryl). The final note takes you to a camp between the Jury Street Metro Station and Evergreen Mills. Both are located due west of Vault 101. You do not need to get these notes to make this Behemoth appear. Keep going west from Vault 101 until you find Jury Street Metro Station. Head further west from there until you find a bunch of wrecked train cars along with a few Super Mutants. If you're having trouble finding it follow the tracks heading NE from Evergreen Mills. The Behemoth should appear after you enter a carriage filled with shopping cart. Locate two carts with a teddy bear inside and open the "cart cage". Finally taking you to the final location where the last (and hardest to find) Behemoth should have spawned. It may also get caught up fighting Talon Company near the Jury Street Station.
 * http://www.youtube.com/watch?v=Lye4wOg6F8s

Note: You can wait up on the edge overlooking the train carts and wait 12 hours and the behemoth will appear, but sometimes Enclave soldiers may appear as well. They will ally with you against the behemoth but once he dies they turn on you. Fawkes can be helpful here as well.

It's also possible to snipe the Behemoth from the cliffs near the entrance to Evergreen Mills. He won't be able to trace the fire back to you and will continue to schuffle around. Blackhawk is a good weapon for this job.

If you want to resurrect the Behemoth from GNR building for another fight, use ID# 1F1F9 (make sure the roof is high).

Appearances
The Behemoth appears only in Fallout 3. A robot also named Behemoth can be found in Fallout Tactics.

Physical Appearance and Equipment
Behemoths are roughly 20 feet tall Super mutants, standing approximately 3 times as tall as a normal human. They have necks so thick with muscle that they merge into their bodies and extremely large build. Some Behemoths carry fire hydrants which can greatly damage the player and swiftly kill any living being in their radius. Their legs are also packed with muscle and provide them with a significant amount of speed, considering their size. Although, the captured Behemoth at Evergreen Mills, apparently, was stripped of all his belongings. They also wield car doors, which are used as shields. The shopping carts on their back may provide some form of primitive protection to cover their thick and bulky hides, or be some sort of package device for their belongings, unlike other Super Mutants which have their own, albeit still basic armor. Another point to consider would be the skulls linked together by a chain to form a necklace of victims, yet another intimidating feature to these already terrifying creatures. Behemoths seem to be pack rats or the super mutant equivalent to a mule, for they carry large amounts of equipment which most likely is stored in their shopping carts. Though, in consideration of the "cart cages" often found at Super Mutant camps, they might also be used to carry captured humans. Smaller companions like Jericho or Clover will rush into battle at closer range (no matter what weapon, they will get close), and if the Behemoth wields a fire hydrant, he will knock them down in one hit, leaving them vulnerable to a quick second attack, an effective two-hit kill by the Behemoth.

Strategies

 * Never stay still as Behemoths are highly effective close combatants and will do significant damage from melee range. Moving backwards while firing is particularly effective. Never let yourself get cornered or stuck on terrain unless you want to be turned into a pile of mush.


 * Behemoths are usually supported by normal Super Mutants. Give the guards priority, but keep moving to avoid being hit by the Behemoth.


 * Due to their large size, it is relatively easy to achieve head shots in VATS. If the player has sufficient first-person shooter experience, it is also not too difficult to achieve head shots without VATS, assuming the gun that player is using does not have significant spread.


 * Due to their large size, Behemoths cannot enter hallways or get under low hanging rubble and have difficulty getting around any large obstruction. The player can use terrain to their advantage to keep themselves out of melee range while gradually taking the Behemoth down at a safe distance.


 * An all purpose strategy for any ranged player is the Dart Gun which will cripple the Behemoth's legs with a single shot regardless of the player's Small Guns skill. With the Behemoth's mobility reduced practically any ranged weapon can be used to finish it off. Care should be taken, a crippled Behemoth can still deal massive damage if allowed to get back into melee range.


 * Small Guns are highly ineffective unless aimed at the Behemoth's head. However, a Chinese Assault Rifle in good condition works fairly well, and can bring down a Behemoth with a handful of mags worth of full auto fire. Keep backing away from the Behemoth while emptying your gun into it, don't use VATS (as it makes you stand still for a second or two after firing). Small Guns specialists will find the Victory Rifle is also efficient and capable of knocking a behemoth down.


 * The Alien blaster and Firelance are particularly useful against Behemoths. With the quick rate of fire and high damage, a non-Big Guns character can take one down before it can get close enough to do any damage.


 * Big Guns specialists with a rank of 100 will find a perfectly repaired Fat Man does 1674 damage per shot and has a potential to knock a Behemoth down. Using one Mini-Nuke and following up with the Minigun while the Behemoth is staggering is a quick and effective strategy. The Missile Launcher is also quite effective at persuading Behemoths to die, and a direct hit to the head with a missile can knock off a decent chunk of its health, even if the launcher is in poor condition.


 * Laying land mines and luring the Behemoth through them is an effective tactic. Bottlecap Mines especially are great because of their high damage.


 * An Unarmed specialist can also fight them barehanded, though dosing on as much chemical assistance as possible is recommended. Behemoths are susceptible to knock-down criticals, though targeting their towering heads outside of V.A.T.S. is much more difficult. Targeting arms for critical strikes can reduce their impact and effectiveness. On hard difficulty, well-timed and frequent stimpack use will be needed to survive the brawl. This is not suggested because the behemoths sheer strength and brute force aggression.


 * If Dogmeat is still traveling with you, order him to stay in a safe place. Dogmeat's only attacks are close range melee and he can be damaged quickly by the Behemoth. This can be dealt with somewhat with the dialogue option to use a Stimpak, which is available even during combat, but keeping Dogmeat out of melee range is safer. This advice actually is also good for any NPC followers you might have, since they will often just stand in place attempting to fight the behemoth.


 * The Terrible Shotgun is particularly effective against the Behemoth as its large size makes getting the entire spread of buckshot on-target relatively easy. If staying that close to the Behemoth is too daunting, bring a companion, preferably one equipped with Power Armor of some kind, to act as bait while the player rapidly unloads a clip into the beast's back. Just be quick, even the most durable companion can't weather that kind of beating for long.


 * But still one of the (or probably the) best ways to kill a Behemoth is the use the wicked power of the Experimental MIRV and kill the Behemoth in one hit.

Actual Size
When initially designed Behemoths may have been smaller, about half the size they are now. The skulls, car doors and fire hydrants they carry are all bigger than any skull, car door or fire hydrant in the wasteland. This is evidence that the Behemoth's size could have been increased after creation. If you spawn a Behemoth they are not the size encountered in-game. Rather, they are only slightly taller than Fawkes.