The Hammers of Dorn is a Codex Astartes-compliant Space Marine Chapter raised from the gene-seed of Rogal Dorn as a Successor Chapter of the Imperial Fists during an unknown Founding, but which dates back no further than the 41st Millennium.
The Hammers of Dorn are stringent adherents of the Codex, and uphold Guilliman's scriptures with exacting precision. This has fostered a great rivalry with the Ultramarines and their Successor Chapters.
Exactly which Founding the Hammers of Dorn Space Marine Chapter were created in is not known for sure, though most signs point to one in the earlier 41st Millennium. Despite their relative youth as a Chapter of the Adeptus Astartes, the Hammers of Dorn have already proven themselves during hundreds of campaigns, including the bitterly-fought Achilus Crusade against the Word Bearers, and the Nightfire Wars against the T'au Farsight Enclaves.
Even amongst the Successor Chapters of the Imperial Fists, the Hammers of Dorn exhibit a veneration of Rogal Dorn to the point of obsession. They take pride in their Primarch way beyond the norm. They believe Rogal Dorn was the Emperor's true favoured son and take great pride in his accomplishments, especially that their Primarch fought side by side with the Emperor during the Horus Heresy.
The Hammers of Dorn upholds the precepts and dogmas of the Codex Astartes with such fervour that its Battle-Brothers go so far as to claim that whilst Roboute Guilliman conceived the Codex, only the warriors of Rogal Dorn can truly master it.
The Hammers are ever seeking to prove their superiority on this point, and take pleasure in pointing out the smallest failings of the Ultramarines and their Successor Chapters whenever they do not match their own militant standards.
The Chapter teachings of the Hammers of Dorn invest a great significance in what they perceive as the rivalry between their Primarch and that of the Ultramarines, even going so far as to extend this rivalry to the present day. While the Hammers of Dorn maintain a non-violent rivalry with the Ultramarines and their Successor Chapters, they hold a very real hatred for the Word Bearers Traitor Legion.
By all accounts, this situation arose when the Hammers of Dorn took it upon themselves to prove their superiority to the sons of Guilliman by taking on their rival's ancient foes. Since then, the Hammers of Dorn have fought the Word Bearers on many occasions, to the extent that they have come to regard them as especially hated foes in their own right.
- The Dread Gestalt (353.M41) - When the Wyrdvane Psykers of the Vostroyan Firstborn 122nd Regiment came through a difficult Warp translation, they arrived in realspace as a gestalt entity of terrifying psychic power. Revelling in their new abilities, they rose up amongst the ranks of their former comrades in the Astra Militarum and enslaved every one of them to their bloodthirsty desires. When the regiment arrived on Sylvanus II they set about the murder of the populace. The Hammers of Dorn were sent on a planetfall mission to destroy the so-called "Dread Gestalt," but the powers of the Wyrdvane Psykers were so swollen that the Space Marine attack was repelled with terrifying ease. Only when the Culexus Assassin known as the Revoker was unleashed into the Vostroyan ranks did the Dread Gestalt lose its power, its individuals flopping back to earth as weak as newborns. They were killed to a man by Vostroyan bayonets even before the Revoker could close with his target to finish the job.
- Achilus Crusade (777.M41-Unknown Date.M41) - The Chapter's involvement in the Achilus Crusade had focused on the worlds known as the Blood Trinity, where the Hammers of Dorn had pursued, without recourse to the Crusade's high command, a series of raids against the Forces of Chaos holding the region. In all probability, the Hammers of Dorn were seeking to ascertain the truth of the rumour that the Word Bearers Traitor Legion was active in the area, pursuing their well-known hatred of this particular enemy. The Chapter recently fought a void-duel against the notorious Chaotic Carnage-class Cruiser Black Grail, though they came off the worse in the engagement and were forced to withdraw, much to their chagrin. The Chapter's forces are currently refitting Karlack, and are by all accounts nearly ready to head out in search of their foes once more.
- The Vaxhallian Genocide (926.M41) - The Chaos Renegades known as The Purge choose the verdant Imperial world of Vaxhallia as their next victim. The planet's surface was soon riddled with consumptive disease and crippling famine. Over the course of a single solar month, The Purge engineered the destruction of no fewer than fourteen billion Imperial citizens. This atrocity did not long go unnoticed; Vaxhallia had served as an astropathic relay hub and a fortress-planet, vital to the defence of the Herakles System. As a result, when the Imperium finally responded, it did so in grand style. The entire Hammers of Dorn, Fire Lords and Crimson Fists Chapters initiated the planetstrike, reinforced by twelve battle-groups of Cadian Shock Troopers and the Imperial Knights of House Raven. Soon Vaxhallia was a roiling caldera of war that drew in forces from across the sector. Vaxhallia's fate grew yet more dire when the plague ship Terminus Est arrived in orbit, disgorging hundreds of Plague Marines and countless millions of Plague Zombies onto the planet's surface. Typhus led this fresh assault and, with each day that passed, more of the Cadians succumbed to the Zombie Plague -- soon the Space Marines and Knights found themselves fighting alone against a tide of Traitors and walking dead. When a second Imperial battlefleet arrived, its commander deemed the world irretrievably lost and began preparations to evacuate the survivors and commence Exterminatus.
- Nightfire Wars (Unknown Date.M41) - The Nightfire Wars were fought between the Imperium and the T'au Farsight Enclaves. The Iron Knights and Hammers of Dorn saw bitter combat in the campaign.
Chapter Combat Doctrine
The Hammers of Dorn maintain a combat doctrine not unlike their Progenitors, with a particular focus on heavy units. They make extensive use of Devastator Squads and Terminator Squads, as well as Vindicator siege tanks and Dreadnoughts, eschewing speed and manoeuvrability in favour of firepower and protection.
The Chaplains of the Hammers of Dorn teach that their Primarch is especially favoured in the eyes of the Emperor of Mankind, for he stood by his father's side during the darkest days of the Horus Heresy. Guilliman and his descendants, these Chaplains preach, cannot lay claim to such a proud deed, for the Ultramarines were fighting against the Word Bearers Traitor Legion on the other side of the galaxy when the Battle of Terra reached its conclusion.
The Hammers of Dorn therefore hold that their Primarch was the pre-eminent son of the Emperor, even going so far as to regard the Ultramarines and the Successor Chapters as somehow lacking. For the most part, the Ultramarines maintain a stoic disregard for what they see as the Hammers of Dorns' somewhat unbecoming, and undeserved self-regard.
To date, the two groups have not actually engaged in honourific combat, though tensions often simmer just below the surface when they encounter one another. The Hammers of Dorn look for rivals amongst both friends and foes alike. Battle-Brothers from the Hammers of Dorn Chapter are wont to be rivals with any allies that are from the Ultramarines Chapter or its descendants.
The Chapter holds the Word Bearers with the utmost contempt, and will go to any lengths to prosecute them and bring them to meet the Emperor's justice if there is even a whisper of their presence in local space.
- Weight of Duty - Weight of Duty is a master-crafted Astartes Power Maul. The flat head of this Power Maul is lined with a miniature grav-plate, similar to those that line the decks of great voidships. Upon striking a foe, the grav-plate activates for a brief instant, multiplying the hammer's impact many times over by increasing its descending weight.
The Hammers of Dorn wear black Power Armour with brass or gold on the trim, helm face and Aquila or Imperialis on the chest guard. The golden squad specialty symbol -- Tactical, Assault, Devastator or Veteran -- is indicated on the right shoulder guard. A white Roman numeral is stenciled in the centre of the specialist symbol, indicating the squad number. Company markings are displayed on the left knee plate.
The Hammers of Dorn's Chapter badge is a modified version of that used by the Imperial Fists, a brass, clenched fist holding a brass hammer superimposed over an Imperial Laurel, also brass. This is centred on a field of black.
- Adeptus Astartes: Successor Chapters (Limited Released Booklet), pg. 50
- Codex Adeptus Astartes - Space Marines (8th Edition), pg. 39
- Codex: Space Marines (8th Edition) (Revised Codex), pg. 35
- Codex: Space Marines (6th Edition) (Digital Edition), pg. 46
- Dataslate: Officio Assassinorum (7th Edition), pg. 39
- Deathwatch: Honour the Chapter (RPG), pg. 136
- Deathwatch: Rites of Battle (RPG), pg. 67
- The Artwork of Clint Langley, pp. 55-60
- Warhammer 40,000: Rulebook (7th Edition), pg. 43