XPN-20A

XPN-20A is a synth living in the Commonwealth in 2287. He is a hostile synth encountered in the Institute's reactor room during the quest The Nuclear Option with any faction. XPN-20A, along with A-2018 and Z4K-97B, will serve as the game's final boss during all endings other than the Institute ending.

Appearances
XPN-20A appears only in Fallout 4.