Hammers of Dorn

A Successor Chapter of the Imperial Fists, this is what you get when you try to out-perform Ultramarines and Red Scorpions. The Hammers of Dorn were created in an unknown founding and are known to maintain a friendly (as in for a given definition of friendly) rivalry with the Ultramarines.

The Hammers of Dorn are ridiculously compliant with the Codex Astartes to the point that they'll call out the Ultramarines on every divergency from the great book of war Roboute Guilliman wrote. They also extend it to other Ultramarine Successor Chapters.

These marines take pride in Rogal Dorn further than any Imperial Fists Successor (as well as the Imperial Fists themselves), for Dorn fought alongside the Emperor during the final stages of the Horus Heresy during the Siege of The Emperor's Palace. This caused them also to believe that while Roboute Guilliman was a great strategist and tactician, only the sons of Dorn are capable of mastering the Codex he written, infuriating the Ultras and their successors (not to mention trying to steal the Ultramarines' boyfriends greatest rivals, the Word Bearers, away from them).

Although it would be seen that they fail at trying to look at the Codex as great book of everything instead of a guide on how marines are supposed to be, they actually were pretty successful at utilizing it in a multitude of campaigns (especially the Damocles Crusade where their rapid adaptability actually gave the Tau problems, at least until Farsight cracked the Codex and used it to predict their every action). One would even suggest that they actually read the Codex from cover to cover and learned how to use every tactic in it while also using their brains. Even though they follow the Codex to the letter, they do put emphasis on firepower and protection (hence their frequent use of Devastators, Terminators, Dreadnoughts and Vindicators).