Lev Tieron was The Chancellor of the Senatorum Imperialis at the time of the 13th Black Crusade. While not a High Lord, the position nonetheless made him extremely powerful and he gained significant influence over his eighty year tenure. During the 13th Black Crusade, Tieron was a key political player in pushing for the dissolution of the vows that kept the Adeptus Custodes bound to Terra.
- 1: Watchers of the Throne: The Emperor's Legion (Novel), Tieron
- 1a: Chapter 26