The BFG9000 is similar to the Plasma Gun (also known as the "Plasma Rifle" and uses the same ammo). But the BFG9000 has a bigger and different design and shoots bigger plasma balls than the plasma gun. And the BFG9000's plasma balls are green and white and cause way more damage. The plasma gun's plasma balls are blue and white. But the BFG9000 has to charge before firing. The abbreviation "BFG" stands for "big fucking gun", as explained in section 14 of the Doom Bible (the pick-up sprite is also labeled "BFUG"). Other expansions of the name were attributed to it before that document was made public, notably "big fragging gun". Characters in the Doom novels refer to the BFG as a "big freaking gun". In the Doom movie, BFG officially stands for "Bio Force Gun" , although Sarge calls it a "big fucking gun". It is also sometimes called the "Blast Field Generator."
The BFG first appears in a secret area of E3M3: Pandemonium. When picked up, the BFG contains 40 energy cell units (80 on the "I'm too young to die" and "Nightmare!" skill levels). It expends 40 energy cell units per shot.
The initials composing the weapon's name stand for "Big Fucking Gun", and in Irish, it is often called the "Big Fecking Gun"; it officially stands for "Bio Force Gun" in the 2005 movie. Alternatively, it also stands for "Big Friggin' Gun".
When the trigger is pulled, there is a pause of 30 tics (about 0.857 seconds) before a green and white plasma ball is ejected. If the large plasma ball hits a solid object, it explodes and causes 100-800 hit points of damage to the target, in round multiples of 100.
After a further pause of 16 tics (about 0.457 seconds), additional damage is calculated: 40 invisible tracer rays are emitted by the player in a cone-shaped area (about 45° half-angle) in the direction the plasma ball was fired (if the player has turned around, the direction of the rays does not change — they are still traced in the direction of firing of the original plasma ball; on the other hand, if he has moved to another location, their origin moves along with him). Each ray causes 49-87 points of damage if it hits a solid object within 1024 map units. Even cyberdemons and spiderdemons, which are immune to blast damage, are affected by these rays.
Therefore, the minimal damage of the weapon is 49 points (if an object is hit by one ray and not the plasma ball) and, hypothetically, the maximal damage is 800 + (40 × 87) = 4280 points (if the plasma ball hits an object for full damage and all 40 tracers also hit the object for full damage). However, even should all 40 rays and the energy ball hit a single target, that much damage can still never actually be inflicted due to the periodicity of the simplistic pseudorandom number generator used by the Doom engine.
Contrary to section 3H of the BFG FAQ, the tracer code does not include horizontal auto-aiming (although, like any bullet attack, each tracer can auto-aim vertically).
Because the BFG projectile does not cause standard blast damage, it is safe for the player to use at point-blank range. In fact, this is often the preferred method of usage against large monsters, as this allows more of the tracer rays to strike a single target for concentrated damage. Conversely, because each ray can strike a different target, a large group of monsters can be damaged by the tracer rays if the weapon is fired from a moderate distance.
Despite its tremendous power, the weapon can be used correctly only with practice, due to its staggered firing sequence and nonstandard blast damage. The BFG FAQ includes an extensive section on deathmatch tactics.
The BFG is particularly useful for killing Arch-viles, due to its ability to quickly dispatch them at close range with no splash damage, as well as Spider Masterminds and Cyberdemons, both of which otherwise require over a dozen rockets to kill. It is also highly useful in tight situations when the player is being assaulted at close range by a swarm of medium-level monsters.
|Damage||100-800 (main projectile)|
49-87 (per tracer)
|Included ammo||40 (80 on skill 1 & 5)|
|Max ammo||300 (600 with backpack)|
|Ammo type||Energy cells|
|Shot type||Projectile (direct hit)|
|25 map units per tic|
(875 map units per second)
|Shots per minute||52.5|
|Thing type||2006 (decimal), 7D6 (hex)|
|Sprite||BFUG (before pickup)|
BFS1 (plasma ball)
BFE1, BFE2 (impact)
|Shots needed to kill1||Mean|| Standard|
|Heavy weapon dude||1.00||0.00||1||1|
|Baron of hell||1.00||0.00||1||1|
(direct hit plus 40 traces)
(direct hit plus 20 traces)
(direct hit plus 40 traces)
(direct hit plus 20 traces)
- This table assumes that all calls to P_Random for damage, pain chance, impact animations, backfire checks, and muzzle lighting are consecutive. In real play, this is never the case: counterattacks and AI pathfinding must be handled, and of course the map may contain additional moving monsters and other randomized phenomena (such as flickering lights). It is also assumed that all projectiles are launched at nearly the same range, so that the various procedures call P_Random in the same sequence each time. Any resulting errors are probably toward the single-shot average, as they introduce noise into the correlation between the indices of "consecutive" calls.
- Assumes that direct hits are possible, which does not occur in any stock map, unless using the idclip cheat code.
The IWADs contain the following numbers of BFG9000s:
|Game||ITYTD and HNTR||HMP||UV and NM|
|The Ultimate Doom||9||9||10|