Fallout might be closely following the canon of the original games, but that doesn’t mean every detail will stay the same. We’ve already learned about Mr. House’s , and it seems the ending of this season will differ from that in Fallout: New Vegas. Because of this, any resemblance to the games still comes as a total surprise — and could hint at something more significant in the future.
In Season 2 Episode 5 of Fallout, one of the game’s most prominent elements has now been made canon, suggesting we might encounter an iconic creature down the line.
Warning! Spoilers ahead for Fallout Season 2 Episode 5.
In Fallout Season 2 Episode 5, “The Wrangler,” Norm and the newly awakened Bud’s Buds leave their vault and head to Vault-Tec HQ, where Norm hacks into a computer terminal to uncover the true purpose of the vaults. On screen, we see the acronym “F.E.V.,” an abbreviation later revealed to be exactly what fans hoped: Forced Evolutionary Virus.
F.E.V. is essentially a way to accelerate evolution, a bright green liquid that, when consumed, causes specific mutations in the user. In the Fallout games, this substance is used by the Enclave (the group behind the science experiments in Season 1 of the series). They employed it to create super mutants, a new subspecies of super-strong (but sterile) creatures that roam the wasteland.
Clues about F.E.V. have been present all along. Remember the odd “cure” Thaddeus took back in Season 1? A major fan theory posits he was actually exposed to F.E.V., meaning his “ghoulification” is really him turning into a mutant. The phrase “super mutant” was even explicitly mentioned in the Season 1 finale, when a West-Tek representative proposed creating “a vault to develop a super-mutant soldier using illegal immigrants.”
What does this mean for the future of Fallout? F.E.V. and super mutants appear in every Fallout game, so this doesn’t hint at anything specific, but their inclusion means the appearance of a live-action super mutant is a matter of when, not if. For many, Fallout isn’t truly Fallout without super mutants, so this might be the big reveal we can look forward to by the season’s end. Perhaps Season 3 of Fallout will explore this key canonical element further.