|Side Quest: Convince the Elders to send help|
|Go to Mariposa Military Base.|
|Hack into Morpheus's terminal and uncover the passage to the Los Angeles Vault. (optional)|
|Go to the Lost Hills and speak to John Maxson.|
|Convince elders to send the Paladins to Mariposa or the Cathedral.|
|Reward: 1500 XP, 2 Paladins at the Cathedral||1500 XP, 3 Paladins at Mariposa|
Go to Mariposa Military Base to become aware of the mutants inside the facility, then exit. If the Vault Dweller wants help at Mariposa, skip to the Brotherhood. If the Vault Dweller wants help at the Cathedral, they must then go to the Cathedral, enter the hall and go upstairs to the fourth floor. Deal with Morpheus and hack his computer. Afterward, proceed down to the basement area and uncover the secret passage leading to the Los Angeles Vault.
After this had been done, return to Lost Hills. Report to Maxson and convince the High Elders about the danger from the base. If the Vault Dweller was at the Cathedral and mentions the controls from it, they will send assistance at their discretion, either to the base or to the Cathedral. Otherwise, the Vault Dweller can only take help to Mariposa.
- If Mariposa is destroyed, the elders will thank the Vault Dweller and the quest will become unavailable.
- Having an Intelligence of one makes completing this quest impossible. An Intelligence of two or three will require the use of Mentats.