Chedorus Iron Legions

During the time when the Legions were loyal, each Iron Legion consists of 1,800 Legionaries made up of 9 companies - called centuries - of two hundred men each. Each Legion can fulfill different roles according to the post-Heresy reforms.
  The Hastati Legions were standard line infantry regiments and where Legionaries of middling experience went. Their purpose was to plug gaps in battle lines and hold taken positions. Despite this, the pure callousness and hatred that the Hastati Legionnaires held made them effective offensive units even without the armor or firepower that a normal regiment would require. This ended with heavy casualties, but that was the way of life for a Legionary.
  The Velite Legions were the light infantry, the screens for more effective units and scouts. New conscripts were always sent to Velite Legions to prove themselves in combat before coming a Hastati, and passing your Velite stage was a badge of honor to all Chedori. Equipped with light armor, camouflage, and small weapons, the Velites were proficient in assassinations and raids on enemy supplies.
  The Triarii Legions were the elite drop shock infantry. Leaping from the back of the Satyr dropships at high altitude and activating grav-chutes at the very last moment, the Triarii would cause massive destruction to unsuspecting enemy forces. Equipped with fast firing lasguns, short swords, and combat shield the Triarii were an assaulting force to be feared. Only the most ruthless Hastati became Triarii, and their enemies compare them more to machine than man.
  No matter the Legion, each platoon of fifty would be led by an Optio, each century led by a Centurion, and the head of the whole force would be the Consul. These Consuls would become members of the Chedorus Senate after their return home, and would be succeeded by their Centurion Prima.
  Other organizations would hail from Chedorus as well, most notably the Armatis Decurions. These would be the tank and APC regiments to support the Legions, made up of five platoons of ten vehicles each. Each regiment would be led by their Decurion, and each platoon led by a Optio.
  When the Iron Legions joined the then Malaxian Dominate (later Blood Cult), the Legions obviously stopped following the restrictions of the Imperium. Many organizations which are called Legions are now mixtures of all the old types, increasing their combat effectiveness without the need for outside support.

Founded after Horus' traitors were pushed back into the Eye of Terror, the Chedorus Iron Legions were the response to the vestiges of Chaos forces left behind. To quell these final rebellions and holdouts, the Iron Legions were trained to be merciless and inspire terror in their enemies. No tactics were too far, no number of massacres too many. Iron Legionnaires would always eventually find their olive green armor stained a deep red.
  Over the millennia, the Chedori have become more and more disgusted with the state of affairs in the Roma Sector. The bloat and corruption had resulted in the complete destruction of several Iron Legions and downturn of the Chedorus economy - no demand for soldiers, no exports by the planet. This all came to a head when in 971.M41 Chedorus declared independence from the Roma Sector's authority.
  The planet was quickly turned into slag by the nearby Imperial Navy forces. Upon the near-complete destruction of their homeworld, the Iron Legions joined with the Malaxian Dominate which has lit the tinder of rebellion in the surrounding systems. The Legions would follow the rogue Inquisitor to the ends of every world, torching all and leaving none alive. Them and their now permanent blood-red armor became the mainline regiments of the Warlord, and they were the dealers of death.
  Upon the collapse of the Blood Cult, many Iron Legions fought to the death. Many more Legions simply disappeared, and there are whispers of them preparing their revenge. No matter which, the Chedori still live upon their shattered world, and still the Iron Legions march.