Seeking to save his family and friends from starvation, MacFadden traveled to the Vault-Tec Agricultural Research Center in April of 2093 to try and restart the facility's Mr. Farmhands for automated agriculture, believing it to be the only way he could help - even when begged to return by Margerie. He was aided by the Responders, who gave him a fusion core to restart the facility's generator. Despite this, he had made little progress even over a full year later due to his lack of skill with robots. His desperation, combined with his lack of skill, led to the Mr. Farmhands going rogue, turning against anyone who breached the facility's boundaries.
MacFadden is mentioned only in Fallout 76.