In the Warhammer 40,000 Universe, the Space Marines are the guardians of humanity. There were origionally 20 Chapters, but fully half of these Warriors turned traitor during the Horus Heresy, turning on their own Battle Brothers. Many of these Chapters, both loyal and traitor, are well known, such as the Iron Warriors, Ultramarines, Blood Angels and the Thousand Sons. However, there are many sub-founding chapters as well, such as the Lamenters, Sons of Medusa, Blood Ravens, Doom Eagles and the Sons of Perseus.

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Lamenters

In the fictional universe of Warhammer 40,000, the Lamenters were an unfortunate chapter of Space Marines who took part, on the losing side, in the Badab War, before being devastated by the Tyranids.

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Scythes of the Emperor

In the fictional universe of Warhammer 40,000, the Scythes of the Emperor are a Chapter of Space Marines who were all but destroyed by the Tyranids. Their armour was black and yellow, with a yellow scythe symbol on the shoulder panels.

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Blood Ravens

The Blood Ravens are the chapter featured in THQ's Dawn of War. They are the chapter which the player plays as during the campaign, and are thought to be a sub-founding chapter from the Blood Angels (although they lack the Black Rage, a distinguishing feature of the Blood Angels) or Raven Guard, but their precise origin is unknown. They include a high number of librarians, but even they do not know why, as their chapter records have been mysteriously destroyed...

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