Darth Shawdon was a male human Sith Lord. He used to be with the New Republic in 15 ABY and he was a Jedi named Sean. Until 15 years later when he was 30 he became too powerful and went and found a planet Ordian ruled by creatures called shorcrof. There he made a small empire with what creatures lived there. While he was making his empire, nobody new where he was.
Until 40 ABY he started his attack and attacked the New Republic. But Shawdon underestimated his power he became to powerful and when he was battling Luke he used his power too much which resulted in an explosion and Darth Shawdon was never seen again.
It was five years later when Darth Shawdon came back to the Republic. He said he didn't remember the name Darth Shawdon and what happened between 30 ABY and 40 ABY. All he remembered is from when he was born to 30 ABY and from 45 ABY to 47 ABY.
When it was 47 ABY he started having dreams about what happened in the time he didn't remember, he told the council and said he will never turn again because too much power is too much.
A few months later he also remembered about how to use his magnificent powers of the Force but he made a promise so he swore to him self he will use it for good, so he used the power to make him live longer and it stopped his age.