By the 41st Millennium a book which apparently had his whole name written down took up an entire volume. Prior to the Horus Heresy, Valdor had earned 1932 names.

Valdor instead wished to raise armies of mortals to be led by his Custodians. Valdor couldn't understand why the Arch-Enemy had decided to spare them, and believed that if they were alive then they would be corrupted. Later Valdor expressed his surprise when Malcador stated that the Primarchs were still alive and that the Emperor was attempting to find them. Surprisingly, Valdor spared Kandawire and let her leave the Palace to retire in peace. During the battle the rebels were crushed and Valdor slew Ushotan, an act he took no gratification in as he had admired the General. Valdor urged the conspirators to surrender, but when they refused he deployed the proto- Legiones Astartes in their first battle. However the conspirators still struck in the Palace Coup, during which Valdor was confronted by Kandawire, as well as Ushotan and his surviving Thunder Warriors. He had become suspicious of Grand Provost Marshal Uwoma Kandawire, dispatching Samonas to unravel her conspiracy before it could begin.

īy the end of the Unification Wars Valdor had emerged as part of the ruling 'triumvirate' of Terra alongside the Emperor and Malcador. During the Battle of Maulland Sen Valdor witnessed the savagery of the Thunder Warriors and became worried over their future. A handful of years later, he assassinated Koja Zu, the Minister of the Anuatan Steppes, and claimed her son, Ra Endymion, for the Legio Custodes. He served during the Unification Wars at the Battle of Maulland Sen. While commonly accepted as the first Custodes Valdor does not recall if he was truly the first Custodian, or simply the first successfully produced one.

Valdor himself knows very little of his past before becoming the Emperor's servant. According to Amar Astarte, his original parents were killed by the Emperor, who moved entire armies across continents to locate and retrieve him. The origins of Constantin Valdor are mysterious.

The king in yellow book