A popular chapter of the [[Adeptus Astartes]] from the [[Warhammer 40k]] franchise, distinguished by their bright red armor.

One of the original Space Marine legions, led by their [[Primarch]], [[Sanguinius]]. While they and most of their successor chapters are normally among the more compassionate groups of Space Marines, they suffer from two distinct flaws: the Red Thirst, which temporarily fills them with an insatiable bloodlust, and the Black Rage, in which a Marine suffers a lasting flashback to the death of Sanguinius and goes completely berserk. The latter is often incurable and sufferers are organized into "Death Companies".