Warhammer 40,000 - Space Marines / Adeptus Astartes
The Adeptus Astartes, commonly known as Space Marines, are the Imperium of Man's elite shock troops in the Games Workshop game Warhammer 40,000.
The founding legions were crafted from the geneseed of demigod-like Primarchs, each with their own personality traits, and in many cases further famous successor chapters like the Black Templars and Crimson Fists have spawned from these founding chapters.
Certain chapters like the Dark Angels, Blood Angels, and Space Wolves also have a unique structure, utilising troops unavailable to other chapters.
The Codex-compliant chapters of the White Scars, Imperial Fists, Iron Hands, Ultramarines, Salamanders, and Raven Guard still have their own individual fighting styles - from the covert ops of the Raven Guard, to the stoic fortification builders of the Imperial Fists.
As so many chapters have been created from these original 9, it's very easy to build your own unique chapter with their own background and colour scheme.