Saduj

Saduj is found in Ultima V, always sneaking around the roof of Castle Britannia in the night, acting suspiciously.

At first Saduj didn't say much. However, after the Avatar identified her/himself as a member of the Oppression by saying the password "IMPERA", Saduj became much more talkative. Saduj was a spy sent by Lord Blackthorn to get possession of the Sandalwood Box, so that Lord British would have no chance to escape dungeon Doom. He then offered the Avatar to join him/her. The Avatar decided to better leave Saduj, as he promised to be nothing but trouble.

Trivia

 * Should the player let Saduj join anyway, he will betray the party in combat as soon as possible.
 * Appropriately, "Saduj" is Judas spelled backwards.
 * Even wors, in Lazarus, Suadj steals the Sandalwood Box and then makes a run for it, meaning an instant game over.