The Onyx Dragons adhere broadly to the Codex Astartes, but their operational structure is adapted to their draconic battle philosophy. The Chapter retains the symbolic pattern of Tactical, Assault, Devastator, Scout, and Command elements, yet the battle companies express those roles through Primaris-era formations, vehicles, jump infantry, Dreadnoughts, and armored transports.

The current company descriptions below reconcile the Chapter's traditional lore with the 3,000-point tabletop identities represented by the uploaded company rosters. The 2nd Company section uses only the 3,000-point roster as its current identity.

The reserve companies of the Onyx Dragons are not idle formations. Each is trained to reinforce the battle companies, hold vital ground, or deploy as an independent strike force when the hunt demands it. Though less specialized than the Chapter’s primary battle companies, the reserves preserve the Chapter’s flexibility, discipline, and ability to answer threats across multiple war zones.