Xaviar

Xavier, initially portayed by Richard Lynch, was a recurring villain on Galactica 1980.

Differing with Commander Adama on how to best bring Earth's technology up to the level of the Galacticans, Xavier went back in time to try and alter history and accelerate Earth's techological development.

In Galactica Discovers Earth he went back to Nazi Germany to try and introduce advanced weapons technology to the Germans. Returning to 1980, he attempted to coopt Professor Mortenson, a nuclear physicist, to participate in his time travel plan.

At the end of that episode, Xavier was determined to have gone back to Revolutionary America to attempt to change history in that period. This apparently also failed.

Xavier's only other appearance in the series was in [{Spaceball]] when he returned to the present to try and ransom the Galactica's children in an attempt to take control of the Fleet. He was played by a different actor in this outing, which was explained to have happened as a kind of disguise that made him appear like Colonial pilot Lt. Nash.

Xavier's ongoing time travel antics were planned to be a continuing sub plot for the series.