Feral ghoul

Feral ghouls, mindless ghouls, ghoul crazies, feral necrotic post-humans or zombies are ghouls (humans mutated by radiation) that lost their ability to reason and have become aggressive animals. They react mostly on instinct, making them very similar to fictional Zombies. Indeed, this similarity has caused much discrimination towards the ghouls that have retained their mental faculties.

Biology
The brain structure of a feral ghoul indicates that the regenerative ability of the neurological systems that affords typical necrotic post-humans their longevity does not extend into the higher reasoning functions of the brain itself. This condition is referred to as "ferocious post-necrotic dystrophy", according to the ghoul physician Doctor Barrows.

As the reasoning and high order thinking portions of the brain deteriorate, the ghoul subject becomes increasingly hostile, giving into a carnal need to feed as opposed to the capacity for thinking and reasoning that a non-feral ghoul retains. It remains unclear exactly what precipitates this change in biology and psychology, but anecdotal evidence seems to indicate that non-social ghouls, or those in isolation, are more prone to the condition.

It is also quite possible that this is a gradual process, meaning that eventually all ghouls would succumb to this condition. However considering the existence of ghouls that have been born prior to the war, it is quite possible that this theory is bunk, or that the rate of degeneration is dependent on the individual and surrounding factors.

One other possibility is that Feral Ghouls have absorbed more radiation than other Ghouls, and this causes brain damage or has another unknown effect to drive them mad. The fact that they have far more severe mutations than normal Ghouls seems to verify this. On a psychological level, they might not have been able to come to terms with their new physical appearance, driving them mad.

Behavior
Feral Ghouls often cluster together in dark, cool environments, like sub-basement-level or totally underground areas, only occasionally leaving their hunting grounds into open air.

Frequently, Ferals will wander from place to place, stopping at fallen prey to feed, but will immediately attack any and all non-Ghoul creatures they come across. Upon detecting a non-Ghoul, most Ferals will make a high-pitched gurgle or screech, and set to search the area. Upon sighting prey, they will often scream once more, alerting any nearby Ghouls, and attack.

One interesting note with Ferals is that they seem to be fooled with rudimentary means. The Ghoul Mask, seemingly nothing more than the hollowed-out head of a Ghoul or several pieces of a human head stitched together, still seems to deter Ferals from attacking.

Controversy
Whether this suggests that Ferals only track through sight, or that their other senses have become dull enough not to recognize prey through movement or scent is unclear, but would explain why Ferals do not attack other, sentient, Ghouls. Their sense of smell will still serve them, but only at a very short range.

What should be of note to the player, regarding what was said above, is that Feral Ghouls are Ghouls that have simply gone crazy. Ghouls were once humans, to be specific; Americans. The reason there are so many in the metro tunnels around D.C. is that after the bombs fell many citizens sought refuge in the tunnels( hence the multitude of desks, beds etc).

It can be concluded Ghouls hunt primarily by sight and sound, like all other creatures in Fallout 3. They don't hunt using other senses because they are human derived creatures. Because of this, the ghoul mask fools them because they see a "Ghoul" and do not (or cannot) use smell to identify them.

Endless Walkers
Endless Walk is the punishment in which a ghoul from the Reservation is stripped of every worldly possession, including clothing, and sent marching into the wasteland. No ghoul has ever come back from the Endless Walk (exiled from the Reservation Otto Stead was saved by governor Dodge at Hoover Dam). Another source of Endless Walkers in the Boulder area is the Crater, the remains of NORAD.

Not all Endless Walkers end up scorpion food, at least not at first. On those rare occasions when one survives more than one year in the wasteland, they turn into wandering, voracious creatures on an endless quest for flesh. Due to their prolonged, open exposure to the desert sun, high radiation, and other hardships of the wasteland, these unfortunate ghouls, who were banished naked from the Reservation, look like walking, sun bleached chunks of beef jerky. Their constant exposure to the hot sun and high levels of radiation has caused their skin to toughen into natural, hardened leather, but at the same time, their brain has completely cooked.

Endless Walkers who have been in the wastes for so long become creatures of instinct and will attack anything that moves in a vain effort to quench an appetite that can never be quenched. Also, their skin is very tough and they strike with their claw-like hands with surprising quickness. Fortunately, endless walkers do not travel in groups. In fact, it is a rare occasion when someone comes across one, though most who travel this side of the wasteland like to keep their distance from the voracious creatures. Though encounters with Endless Walkers are rare, when someone does encounter them, they are assured to never forget the encounter, if they survive.

Appearances
Feral ghouls appear in Fallout (in random encounters, as "mindless ghouls"), Fallout 2 (as "ghoul crazies") and Fallout 3 (where they are actually named "feral ghouls" for the first time).

Fallout 3
Feral Ghouls in Fallout 3 come in 3 leveled varieties. They are quite fast, and will charge the player at surprising speed once they detect the player.


 * Feral Ghouls are the weakest; naked and noticeably weaker than standard human opponents, they are easily dispatched with one or two headshots from any decent weapon. It's possible to identify the difference between male and female Feral Ghouls. Males (presumably) have rags only around their waists, while female ghouls have the remains of shirts on as well.
 * Feral Ghoul Roamers wear what appears to be the remains of combat armor, and are somewhat tougher than standard Feral Ghouls, being roughly on par with mid-level human opponents in terms of durability (i.e. requiring about 3 or so hunting rifle headshots to kill). It is possible that Roamers are ghoulified U.S. soldiers as they wear Combat Armor.
 * Glowing Ones are the rarest and "highest ranking" Feral Ghouls; they have even higher durability than Feral Ghoul Roamers, and can take several hunting rifle headshots before expiring. Additionally, they periodically emit a 360 degree pulse of radiation that damages human enemies and heals any nearby Ghouls.
 * Fearl Ghoul Reavers are the new top dog introduced in Broken Steel. The are much more combat-worthy than the others, and even have the ability to throw grenades.

Strategies
Most Feral Ghouls should be dispatched from long range before they can do any harm. However, they have a tendency to attack from behind so carrying an assault rifle is a good opportunity because if they get close you simply enter V.A.T.S. and aim for their head (which has a mysterious tendency to come off, probably due to decomposition). Since they run in straight lines they aren't difficult to hit and the assault rifle is a good weapon for riddling them with bullets. Their movement patterns also make them prime targets for mines--they will run right into them if the path over the mine is the quickest way to get to the player. If you have a Laser Rifle or Hunting Rifle though, you'll have no trouble. With some basic Small Guns skill you can use a combat shotgun to easily dispatch swarms of feral ghouls, by strafing and shooting you can quite easily kill them without taking much damage. With decent skill, melee weapons are also quite efficient. They are actually quite easy to kill once the player has noticed them, but Feral Ghouls & all their variants have nearly silent footsteps & move at high speed. Once they notice an enemy they will snarl characteristically, but after that they make little noise.