Here I'll give a brief of example of what we currently don't know of the Zetans.
Through the study of existing notes and computer terminals, players have weeded out the true origins and history behind a lot of the series' main contenders such as Vault-Tec, The Brotherhood of Steel, and more, but without more information, the Zetans are lost on us.
Therefore, with so many questions to be answered, it seems only logical to include a new Zeta-esque DLC for the Fallout series. We also know that they have extremely advanced weaponry which has made an appearance in Fallout 4. What, exactly, do we know about the aliens of the Fallout universe? We know that they are ponderous, beaming several generations of people for study into Mothership Zeta in the Fallout 3 add-on.
