Mutant Hound

These mutant dogs differ greatly from their domestic and rabid cousins. While the latter often turn rabid due to radiation exposure, mutant hounds are not nat- ural creatures. They are created through exposure to the Forced Evolutionary Virus. They are several times larger than normal dogs, with an increased muscle mass and aggression, and suffer detrimental effects of lowered intelligence seen in super mutants. Their skin is often a patchy green color and they lack any fur. They are almost always found in the company of super mutants, who use them as guard dogs. It is unknown if this is their primary purpose, or if like humans, super mutants keep them for companionship.
“Super Mutants are often accompanied by Mutant Hounds, monstrous dogs that are just as dangerous as their masters.” — Fallout 4 loading screens
Mutant hounds or FEV hounds are creatures found in the Commonwealth and are present on the Island in 2287.
Background These are dogs that have undergone major mutations from being exposed to the Forced Evolutionary Virus. Usually, they are accompanying super mutants. They may have been created in the FEV lab of the Institute, along with the rest of the super mutants that are seen throughout the Commonwealth.
Biology Mutant hounds are usually several times bigger than normal stray dogs and mongrels. The modification imposed on their bodies by the Forced Evolutionary Virus is similar to the one the super mutants went through: increase of muscle mass, depigmentation of the skin to a greenish color and complete loss of body hair.

SPECIAL ABILITIES
IMMUNE TO RADIATION: The mutant hound reduces all Radiation damage suffered to 0 and cannot suffer any damage or effects from radiation.
IMMUNE TO POISON: The mutant hound reduces all Poison damage suffered to 0 and cannot suffer any damage or effects from poison.
KEEN SENSES: One or more of the mutant hound’s senses are especially keen; they can attempt to detect creatures or objects which characters normally cannot, and they reduce the difficulty of all other PER tests by 1 (to a minimum of 0).
WARNING HOWL: During the first round of combat, a Mutant Hound may howl as a major action. Each super mutant or Mutant Hound within Long range may make a second minor action on their next turn. No NPC may benefit from this ability more than once per combat.
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