Originally created before the Great War by the government to supplement human troops in battle, deathclaws were derived from mixed animal stock, primarily from the very common Jackson Chameleon. They were then refined by the Master, using genetic manipulation and the Forced Evolutionary Virus. The resulting creature is incredibly fast and powerful. Around 2161, deathclaws were still considered mysterious and legendary creatures to many. They could originally only be found in the Boneyard at the warehouse, living with their mother. Later, as the deathclaw population grew and began to spread across the continent, the deathclaws stopped being perceived as legendary beasts, and started to be seen just as another dangerous creature.
Deathclaws come in many forms, and variants, such as Intelligent Deathclaws, or Baby deathclaws. Following this will list a few that may be found, but not including unique deathclaws, like Stripe, or Rawr.
Deathclaw: The most common type of deathclaw, these exist throughout the wasteland, and they are feared throughout. As mentioned above, they are highly difficult to defeat, due to high health, high movement speed and lethal melee attacks. Their social nature adds to their lethal image: it's not uncommon to encounter regular deathclaws in groups of three or four.
Mother Deathclaw: Female deathclaws, also called mothers or matriarchs, are fewer in numbers. Only one female is the pack mother at a given time, with another female taking her place when she dies. Mother deathclaws can be distinguished from males by their dark blue color, barbed tails and back swept horns. They also seem to have a bloated abdomen, presumably from eggs, and are generally larger in size than normal deathclaws. If her young are killed, she will go into an uncontrollable rage, killing anything nearby, excluding other deathclaws.
Baby Deathclaw: Baby deathclaws are the smallest and weakest form of deathclaws. They will tend to stay close to and follow their mother, and protect her when she is either threatened or attacked. If the mother is killed, the baby deathclaws will surround her body and attempt to protect her.
Intelligent Deathclaw: In 2235, the Enclave captured many deathclaws and exposed them to FEV. This boosted their intelligence, giving them the ability to talk with varying degrees of erudition and articulation. This subspecies was highly intelligent, about the equivalent of an eight-year-old, with some even being on par with average adult humans. Their learning capacity was very high and they were capable of abstract thought and reasoning. Although they did not have vocal cords, the deathclaws seemed to mimic human speech in the same way a parrot does. Socially, they had a rigidly hierarchical, peaceful, pack-based ethical code. They were extremely loyal to the pack as a whole, treating it as a family unit rather than having individual families. Fights within a pack are unheard of, and the pack's leader controls many aspects of life.