The Dreadnoughts which serve the Deathwatch are different from the "standard" Space Marine Dreadnoughts in some respects. First, unlike other Marines who are seconded to the Deathwatch, Dreadnoughts are separated from their parent Chapters forever, as they take on the Long Vigil. Secondly, they may wield unconventional combinations of weaponry or equipment to exploit the weaknesses of a particular Xenos foe.
Rare as it is for a Space Marine to be revered enough to become an Old One, it is rarer still for a member of the Deathwatch to achieve the same honour. The circumstances of the small unit actions undertaken by Kill-teams often make it impossible to retrieve a fatally injured battle-brother and inter them within a sarcophagus in time to be transported to a fortress. Even if this is achieved the Space Marine must be worthy and willing to remain with the Deathwatch, effectively renewing their vows to serve with the Watch in perpetuity. Finally, permission must be sought and received from the Space Marine's own Chapter that he may remain with the Deathwatch.
The Deathwatch possess only a handful of Dreadnoughts in fortresses scattered across the galaxy, and many Old Ones are preserved for their unique knowledge of fighting different xenos. Apart from possessing the deadly combination of hatred, experience and machine hardiness, the Deathwatch Dreadnoughts are sometimes used as repositories of lore, archives for the ghosts of old campaigns against extinct xenos and Kill-team operations of centuries past. The value of the Old One's knowledge to the Deathwatch cannot be overestimated. Across the vast volumes of space overseen by the Deathwatch, contact with some species of alien can come centuries apart, making an eyewitness to previous encounters invaluable. On other occasions warp storms will slacken to reveal whole systems unseen by man for millennia but still remembered by the Old Ones that fought there long ago. In the past, xenos thought long extinct have emerged from the dust to assail humankind once more, and the Old Ones have been able to vividly recall every detail of them, every strength and weakness they revealed and each blow struck to lay them low. In all of these circumstances an Old One can bring incredible clarity and sharp-eyed perspective to the dry reports and corrupted records that can be unearthed from musty data-vaults.
It is a rare and valued Kill-team that is accompanied by a Deathwatch Dreadnought into the field. Such a precious resource is only risked at times of greatest peril and on missions that would be doomed to failure without their unique capabilities. Most Deathwatch Dreadnoughts follow the traditional weapon configurations handed down over uncounted centuries, like the Deredeo with its power claws and heavy flamers, or the Furibundus with its twin-linked lascannon and Cyclone missile launcher. At times of special need, however, Deathwatch Forge Masters have created many of their own armament variants based on these sacred designs but more suited to exceptional environments and particular xenos foes. In ages past, Deathwatch Dreadnoughts have been equipped with siege hammers expressly for the purpose of overcoming Ork fortifications, outfitted with quad autocannons for bringing down Eldar raiders and mounted with additional flamer batteries for clearing Hrud warrens. Such egregious interference with the sacred form of the Dreadnought does little to assuage the concerns of more traditionally-minded Chapters about the practices of the Deathwatch in this field.
A Kill-team blessed with Dreadnought support can face some unique challenges. A silent approach, for example, becomes almost impossible without extensive use of Stummers or other specialist equipment. The local terrain must also be capable of supporting the tremendous weight of the machine. In practice a Dreadnought is commonly kept in reserve, coordinating operations from an orbiting vessel. Once the enemy has been located the Dreadnought is normally inserted directly into combat via drop pod, Thunderhawk gunship or teleportarium.
Notable Deathwatch Dreadnoughts
- Aeton Macramus, Venerable Dreadnought
- Axcillian - formerly of the Eagle Warriors
- Chyron - formerly of the Lamenters, member of Kill Team Talon.
- Nihilus, Venerable Dreadnought
- Rahellion, Redemptor Dreadnought
- Symio, Venerable Dreadnought
- Szobczak - formerly a Techmarine of the Imperial Fists, now an Ironclad Dreadnought