Space Marines, also know as Adeptus Astartes (Legions Astartes before Horus Heresy) is transhuman soldier created after their precessor, Thunder Warriors by the Emporer himself. Them are created from the genetic material of Primarchs. They took part in the Great Crusade, reunited humankind under a single banner leading by the Primarchs later found by the Emperor, until the warmaster Horus Lupercal betrayed the Emperor. After the Horus Heresy, traitors fleed to the eye of Terror while the loyal Legions divided