Cawl himself is over ten thousand years old, though how exactly he has sustained his life for so long is unknown. It is thought that he has used forbidden alien methods technology with mechanical bionics to sustain his life at the cost of any humanity he may have had left.[5a] After the Horus Heresy he was charged by Roboute Guilliman to oversee two great tasks should the Primarch fall. They were to be the resurrection of Guilliman and the creation of the Primaris Space Marines with the Sangprimus Portum, two things he worked on for the next 10 millennia.
At the time of the 13th Black Crusade, Cawl was guided by a Harlequin Shadowseer to a planet which was long-abandoned during the 4th Black Crusade. After battling Orks on the world he recovered an artifact and learned of the Pylons holding back the Immaterium. He was then instructed by this mysterious Shadowseer to go to Cadia, where he aided in the defenses of the world against the forces of Chaos. He was eventually joined into a reluctant alliance with the Necron Lord Trazyn the Infinite and the duo joined together to activate Cadia's Pylon array. While initially successful in activating the Pylons, Cadia was shattered by Abaddon's redirection of the remains of a Blackstone Fortress into the planet. Cawl fled the Cadian system with his artifact and several allies including Saint Celestine, Inquisitor Greyfax, and Marshal Marius Amalrich. Hounded by the Black Legion who sought his artifact of still unknown significance, Cawl and his allies were eventually guided into the Webway on Kalisus by his saviors: Eldar under Eldrad Ulthran.
The Eldar guided the expedition to Macragge where Cawl revealed that his precocious artifacts were the Emperor's Sword and a suit of Power Armour that could heal the comatose Primarch Guilliman. During the Ultramar Campaign Cawl was able to successfully work with the Eldar in resurrecting Guilliman, who drove the Chaos invaders from Ultramar. Cawl accompanied Guilliman in the subsequent Terran Crusade and was one of the few to reach Terra. Once on Terra Cawl talked with Guilliman of a secret pact with Mars and of his work nearing completion. He then made his way to the Red Planet to oversee its success.
This secret project was Cawl was revealed to be the creation of Primaris Space Marines, the next generation of the Angels of Death. In truth, Cawl had been working on the project for 10,000 years. Despite his seeming loyalty and effectiveness, Guilliman still harbors a great amount of distrust for Cawl. He believes Cawl to border the heretekal, particularly with regard to his creation of an artificial intelligence known as the Cawl Inferior. Due to this, Guilliman has repeatedly refused Cawl's requests to become Fabricator-General. Cawl's actions have also made him enemies with many across the greater Mechanicum, particularly the more religious and conservative Tech-Priests.[5a]
Cawl often speaks to Guilliman through an Artificial Intelligence known as the Cawl Inferior. The Cawl Inferior is a being made up of hundreds of Servitor heads and is capable of perfectly mimicking Cawl, though it insists it is a different entity entirely. The intelligence also insists it is not a true artificial lifeform but Guilliman has his doubts and believes the device might be lying or deliberately understating its own capabilities.
- 1: Gathering Storm – First Look
- 1a: pg.120
- 2: Gathering Storm: Fall of Cadia
- 3: Gathering Storm: Rise of the Primarch
- 4: Warhammer community
- 5: Dark Imperium (Novel)
- 5a: The Cawl Inferior