When the Sith Empire's invasion of the planet Corellia was carefully planned over a number of years during the Cold War and the renewed conflict, Nadien was approached by the First Son of the Sith Emperor who helped convince him and the Council to join the Empire by revealing his identity as Syo Bakarn, a Jedi Master and member of the Jedi Council.
In 3641 BBY, Nadien stood alongside Councilors Saiak and Delquis when the trio were approached by the Barsen'thor. Demanding to know where the First Son was, Nadien tried to explain before Saiak, who was revealed to be a Child of the Emperor, kills Delquis which frightened Nadien. After Barsen'thor killed Saiak, Nadien feared that he could be a Child as well, but kept his hopes up when he revealed the location of the First Son.
- Star Wars: The Old Republic (First appearance)