Deathclaw (Fallout: Brotherhood of Steel)

The experimental deathclaws are a group of deathclaws unique to Secret Vault, a Vault-Tec installation which served as the company's ticket to a life after the apocalypse. Aside from many scientific projects that were to insure the company's power, some research with radioactive materials and FEV took place there. When the Initiate of Brotherhood of Steel visited the Vault, he encountered unique variants of the beast known all over the wastes.

The Vault-Tec scientists apparently obtained a sample of the deathclaw bioweapon and tried to improve it, using FEV, radiation and technology. The new species become larger, stronger, gaining extra muscle mass and a type of exoskeleton with many protruding spikes. However, the mutation led them to become blind, leaving the deathclaws to rely on their other senses. The longer they live, the bigger they become, so their mutation and the FEV effect could be very similar to that of Capital Wasteland super mutants. The eggs of these deathclaws are also unique, as they appear more like a pile of flesh nearly the same size as human.

Baby deathclaw
Secret Vault's baby deathclaws are easy to kill, as they are small, their claws are weak and their skin still has no exoskeleton.

Deathclaw
This deathclaw looks at least a bit like his normal relatives from the West Coast and Capital Wasteland, but much heavier and stronger.

Large deathclaw
The oldest of the Secret Vault deathclaws. They are grey, brutish, and slow.

Stealth deathclaw
These nightmarish creatures are probably the result of integration of a stealth device (like Stealth Boy) inside the body of a deathclaw. They could become invisible but still quite recognisible in the air due to their speed and size.

Adolescent deathclaw
A prototype variant of a deathclaw. This particular young deathclaw was a subject of an experiment that made him a living colossus. He is the biggest of all the deathclaws, even bigger than Super Mutant Behemoth. It is presumed that FEV made him to become such a threat.

Mama deathclaw
The Secret Vault deathclaw mother is grey, big, with highly developed exoskeleton. Her head is protected by a natural crown and she has a lot of spikes coming out from her back. She also has a strange ability to regenerate from radioactive pools found in her den, which is probably is result of modified FEV's regenerative features.