Sapphon

Sapphon is the Grand Master of Chaplains of the Dark Angels Chapter of Space Marines. Also known as the Finder of Secrets', Master Sapphon did not receive this esteemed rank of Grand Master due to age or ability as an Interrogator-Chaplain (Master Asmodai is superior in both), but because of his ability as an inspirational leader of men. Even the brave and indomitable warriors such as the Dark Angels are inspired by Sapphon's presence when he is amongst them on the battlefield. His presence inspiring them to carry out feats of extraordinary valour.

Source

 * Codex: Angels of Death (2nd Edition), p. 82