Valentus Dolor was a member of the Ultramarines during the Great Crusade and Horus Heresy. One of the Tetrarchs, Dolor ruled the planet Occluda and served as Champion of Primarch Roboute Guilliman. He also commanded the secret police of Ultramar, the Vigil Opertii.
During the Heresy, Dolor was the one who discovered the body of Vulkan on Macragge. After Imperium Secundus was abolished and Guilliman, Sanguinius, and Lion El'Jonson attempted to reach Terra through the Ruinstorm, the Realm of Ultramar was left under the Regency of Dolor.
- 1: The Unremembered Empire (Novel)
- 2: The Horus Heresy Book Five pg. 81
- 3: Ruinstorm (Novel) Chapter 1