World Eaters - Specialised Ranks and Formations: Devourers - The Devourers were the premier cadre within the World Eaters Legion that served as a dedicated bodyguard unit for their Primarch Angron (whether he needed one is another matter). In battle they fought encased in Terminator Armour and carried the most savage weapons the XIIth Legion possessed. This warrior band had only twelve members, and access to its ranks was only attained by defeating a Devourer in single combat to the death or, should one of its number fall in battle against an enemy, a successor was selected by a contest open to all Astartes in the XIIth Legion, only one of which would survive.Rampager Squads - Rampager Squads were near-berserker assault units composed of the most savage and bloodthirsty World Eaters Legionaries who had undergone the dangerous psycho-surgical procedure of having a cortical implant inserted within their brains and who were deemed too unstable to serve in a regular line unit. Within these units, a small minority of those Legionaries that were too far gone to be anything but restrained by force between battles became known as the Caedere or the "Butchers". Others focused their desire for berzerk slaughter through martial discipline, mastering a variety of macabre and savage weapons patterned from those used by Angron's fellow arena gladiators and found on the Feral Worlds from which the XIIth Legion primarily drew its recruits during the Great Crusade.Red Butchers - On the killing ground of Istvaan III, there were World Eaters on either side of the conflict who succumbed utterly, devolving into mindless frenzied savages that could not be controlled. Rather than euthanising such individuals as had happened in the past, the Apothecaries had the mad subdued and chained for a far darker fate. The Techmarines made customised Terminator suits from recovered wargear for them, fashioning them as both armour and as confinement; mechanised prison cells that could be immobilised with a remote signal. Hung in chains in the holds of the World Eaters' warships, foaming and screaming in impotent rage, the Red Butchers were born.Red Hand Destroyer Assault Squad - Amongst the XIIth Legion, those who proudly bore the mark of the Blood Hand -- or as it was known by some, the "Butcher's Mark" -- upon their armour would be drawn together, not through brotherhood or camaraderie, but through rivalry and enmity. The symbol, held in higher regard than almost any other honour or accolade borne by the World Eaters, marked these individuals out as having demonstrated exemplary ferocity or violence in the name of the Legion, be it through the sheer number of enemies butchered in battle or through the taking of the head of a foe of superior rank in single combat. Amongst the Destroyer companies of Angron's Legion, those warriors who bore this mark formed cohorts known amongst their brethren as "Red Hand" squads. As the Horus Heresy unfolded, these squads would consistently take their place in the vanguard, roaring inhuman cries of bloodlust as they sought to prove themselves ever-worthy of bearing this gory embellishment.Destroyer Squads - Considered dishonourable by some Legions who made little use of them or eschewed them altogether, the Destroyers were equipped with and expert in the use of otherwise proscribed and forbidden weaponry. Alongside certain factions of the Mechanicus, only Destroyer cadres had the license to use these weapons in the forces of the Imperium by the Emperor's command. Rad-weapons, bio-alchem munitions and the crawl-burning horror of Phospex were among the Destroyer Squads' dark arsenal, weapons which irrevocably tainted the ground upon which they were used. Marked by their fire-blackened and chem-scalded armour, Destroyers were often shunned and deemed somehow tainted by their Battle-Brothers in many Legions and were considered at best a necessary evil, although the effectiveness of their relic-weapons in cracking especially difficult enemy defences could not be denied.Triarii - The Triarii were 5 full companies of the XIIth Legion's finest shipboard warriors who excelled in void warfare and boarding actions, commanded by Centurion Delvarus, the undisputed pit fighting champion of the World Eaters. These warriors were honour-bound to protect the World Eaters Legion's flagship, the Conqueror.