Fawkes is an intelligent super-mutant found in Vault 87, which is encountered during the "Finding the Garden of Eden" quest during the main story. The player encounters the mutant while working his/her way through the vault, and is surprised when he begs to be released from his cell.
Locked up by the other mutants for his unusual intelligence, which they mistrusted, Fawkes was able to attain literacy and knowledge by using the terminal in his room. He does not remember anything in particular from his former life as a resident of the Vault, with the exception of some knowledge regarding the layout of Vault 87 itself. He got the name 'Fawkes' after reading the story of Guy Fawkes, and adopted the name as his own.
He offers to retrieve the GECK from the irradiated room it was held in if the player had kept him on thus far, but parts ways afterward, claiming that, as a super-mutant, he would be unwelcome in any town the player chose to visit. However, he returns to aid the player after the end of "The American Dream" quest, and helps the Vault Dweller escape from Raven Rock, and joins as a normal recruitable character from then on, as long as the player has good karma. He carries a Gatling Laser and a Super Sledge to fend off enemies.
Interestingly enough, no one in any town seems to take much offense to the presence of the mighty super-mutant, despite his previous worries.
Fawkes was voiced by Wes Johnson.
While looking through the Chief Physician's terminal many players were surprised to find out the person originally locked up in Fawkes' cell was a woman. This lead to speculation on Fawkes' gender because the FEV virus mutates humans into a single, asexual state.
Fawkes, however, claims he wasn't the original resident of the cell and he was locked after the original subject died.
On the official Bethesda forums, Emil Pagliarulo confirmed Fawkes was male before turning into a super mutant.
- Fawkes is probably the best companion in the game for one reason, not counting the fact that he is a super-mutant that's actually nice to you, he can take on a Super-Mutant Behemoth on his own, hardly losing a single health bar. In fact, Fawkes is completely invincible. He carries two weapons. A large sledge hammer for melee combat, and laser Gatling gun for ranged combat.