Viscious

 is a super mutant commander in the Master's Army in 2161.

Background
Viscious oversees the operations center in the LA Vault and controls access to the Master. He has an unhealthy smoking habit, although given the longevity and resilience of mutants, the probability of him developing cancer is slim.

Interactions with the player character
Viscious will attack the player on sight, if he has his weapon drawn, even if he wears Cathedral purple. Otherwise, he might question the presence of the player in the Vault and either direct him to the Master, for a nullifier or attack him.

If not killed directly by the Vault Dweller, he is still killed when the Cathedral is nuked.

Appearances
appears in the original Fallout.