Dog

Dogs are creatures found across the post-War United States. Many have remained domesticated pets, but many more have turned feral and hunt the wasteland in packs. The dogs that survived the War are a larger and tougher breed, now almost wolf-sized. Even so, just as they have in ages past, many dogs have remained faithful and beloved companions to men and women. Inarguably, the most famous of these post-nuclear canines was Dogmeat, the companion of the Vault Dweller, and his descendant, the companion of the Lone Wanderer.

Background
The domestic dog (Latin: Canis lupus familiaris) is a canid that is known as man's best friend. The dog was the first domesticated animal and has been widely kept as a working, hunting, and pet companion. Though most breeds of dogs remain largely un-mutated by radiation exposure, some modified or mutant varieties do exist. The Master created centaurs by mixing dog, human and brahmin in the FEV vats. Fallout Bible 1 Fallout Bible 0: "3. Are the radscorpions a product of the FEV virus? When you talk to the doctor, Razlo, in Shady Sands, he tells you that they were once American Emperor Scorpions but that he has no idea how they mutated because radiation alone couldn't have done it.  For that matter, what about all of the other creatures of the wasteland?  Which ones have been mutated by FEV and which ones haven't?  Maybe in the bestiary each creature could have a stat that shows it's level of FEV infection." "Answer: Mantises. Most species of rats. Gecko lizards. Brahmin Scorpions Ants Various varieties of plants, including the Venus Flytrap. Rumor has it some dogs were affected, but no one's seen any, so for now that's just rumor. Of course, the centaurs are a mash of human, dog, and various other parts... but hey, who knows how that mutation came about. Grey was probably messing around in one of his labs.
 * The radscorpions are a result of a combination of radiation and the FEV virus, and Razlo in Shady Sands is correct - they were originally Emperor Scorpions that have grown... big.
 * FEV-Infected Critters in the wasteland include almost all the ones you've seen in F1 and F2:
 * Creatures not mutated by FEV probably did not survive the aftermath of the Great War, with the possible exception of cockroaches... and perhaps normal ants, though there are FEV-infected versions of these species.
 * No one knows where those bird noises in Vault City came from.
 * I'll try to include a chart of FEV-infected creatures in future additions as well as other critters that you may not have seen in F1 and F2. Most likely a great majority of insects were affected (they tend to breed much faster, and their mutations tend to become evident pretty quickly as the generations advance), possibly beetles, some spiders, cockroaches, and other creatures." Dogs were also subject to cyberization, which resulted in cyberdogs. Toy breeds of dog such as poodles are virtually nonexistent in the post-War world. 

Dog


Regular dogs with standard statistics and characteristics but no special attributes.

Legion mongrel


Legion mongrels are dogs owned and bred by the houndmasters of Caesar's Legion. Mongrels are mainly used in combat and scouting missions by the Legion. Because of their thick, shaggy hair (as seen in the picture) and their red-colored eyes, they are of a distinctly different breed than most dogs found in games.

Vicious dog


Vicious dogs are a nearly hairless and apparently, partially ghoulified species of wasteland canine. Ruthless survivors of the wastes, these starving, irradiated mutts will attack anything that moves.

Mongrel


Mongrels are terribly irradiated, mutated forms of dogs. They are red and ghoulish and usually hunt in packs randomly found throughout the Commonwealth and Appalachia. There are many variants of mongrels, the worst of which are the alpha variants.

Mutant hound


Unlike other species of dogs mutated by radiation, these dogs are also mutated by FEV, giving them a distinct rough green exterior. They hunt with super mutant packs and they also come in a glowing variant.

Appearances
Dogs appear in all Fallout games, as well as on the cover of the graphic novel All Roads.