Location from Fallout by Interplay / Bethesda
The cursed birthplace of the Brotherhood of Steel and the super mutants — where the pre-War government's darkest experiment turned soldiers into rebels and prisoners into monsters.
The base smells wrong — a chemical sweetness undercut by biological decay that no amount of time has erased. The FEV vats still bubble faintly in the deepest chamber, their green glow providing the only light in corridors where the electrical systems failed decades ago. Footsteps echo in ways that suggest the tunnels go deeper than the maps show. The ghosts here are metaphorical but heavy: this is where Captain Maxson discovered the government was experimenting on prisoners and led his unit in rebellion, founding what became the Brotherhood. This is also where the Master dipped humans into FEV to create his super mutant army. The same building birthed both order and chaos.
A partially collapsed military installation built into a mountainside, its blast doors hanging open on broken hydraulics. The exterior is a concrete bunker entrance surrounded by dead earth — nothing grows within a hundred yards. Inside, the corridors are industrial military: reinforced concrete, heavy steel doors, decontamination chambers with shattered glass. The deepest levels house the FEV vats — massive tanks of sickly green liquid, some cracked and leaking, their contents having seeped into the groundwork. Radiation and biological contamination make the lower levels lethal without protection. Pre-War military equipment lies scattered and corroded.
Also known as: Mariposa, Mariposa Military Base, The FEV Facility, West Tek Facility