Grey Knights - Chapter Brotherhoods: The bulk of the Grey Knights Chapter is organised into "brotherhoods," fighting formations roughly equivalent to the Battle Companies of other Space Marine Chapters. The Chapter comprises 8 such brotherhoods, each corresponding to one of the 8 Astartes "Titans" and former Knights-Errant that were chosen by Malcador the Sigillite and the Emperor to be the initial core of the Chapter at the time of the Horus Heresy.On paper, each of the Chapter's brotherhoods contains roughly one hundred battle-brothers under arms, though this nominal figure does not include the brotherhood's officers: the brotherhood's brother-captain in active tactical command, the brotherhood's Champion, Ancient, other officers who may act in support and the Grand Master who holds final responsibility over the brotherhood.Each brotherhood is divided up into the various squads and formations of the Chapter. These each fall into several broad categories focused on the different fighting methods and specialised wargear used by the Grey Knights.As with other Space Marine Chapters, the Grey Knights of each brotherhood are primarily organised into squads of ten battle-brothers, each of which can then further divide into two "combat squads" of five should the mission's tactical requirements so dictate.A Grey Knights squad is considered to remain effective with only five of its members battle-worthy, so with a small amount of duty reassignment and doctrinal flexibility, a brother-captain can keep his brotherhood at an acceptable fighting strength, even with up to a third of his warriors out of commission.Decisions concerning the exact breakdown of squad type within a brotherhood rest entirely with its brother-captain and Grand Master. However, it has long been proven that a rough tactical balance of squads -- between three and seven operational units each of Terminator, Purgation and Strike Squads -- is by far the most effective combination. Accordingly, all but the most maverick of Grey Knights commanders follow this example, and make only minor changes to suit their tactical preferences.Regardless of role, all Grey Knight squads draw their equipment from the same Armoury of Nemesis Force Weapons, grenades, Storm Bolters and psi-enhanced heavy weapons. Each squad also independently practices its own psychic disciplines, the better to allow mental and physical prowess to act in reinforced harmony.The only drawback to this organisation is that when a Grey Knight moves from one type of squad to another he must learn anew how to wield his psychic potential in battle, suppressing all other applications he has learned to that point. Each of a brotherhood's squads is led by a "Justicar," a Grey Knight who holds a rank equivalent to that of a standard Space Marine sergeant.It takes a powerful mind to lead other Grey Knights in both battle and psychic unity, and only the most adept battle-brothers rise to this honoured rank. In addition to his bonds of leadership, it is the Justicar's duty to hone and focus the psychic powers of the battle-brothers he leads and to act as the conduit for their abilities. Such a role places the Justicar in greater danger than his fellows, for as the squad's mystic focus he will be the first to suffer should things go awry.During his career, a battle-brother of the Chapter will take on many different roles, from serving in the Terminator Squads with blade and Storm Bolter to the more lightly-armoured Strike Squads or heavily armed Purgation Squads. It is the responsibility of every Grey Knight to become skilled in all of the weapons used by the Chapter, just as he must hone his psychic powers into a mystic blade with which to cut down Warp-spawn.All battle-brothers are trained in the use of every piece of wargear and armour possessed by the Chapter. Thus it is possible for a battle-brother to serve in different types of squads from one mission to the next.1st Brotherhood ("The Swordbearers") - Grand Master Vardan Kai commands the 1st Brotherhood with Cadrig Pelenas as its brother-captain. As Kai is also the Chapter's Steward of the Armoury, his brotherhood is often called upon when the Grey Knights require large numbers of Stormravens or Land Raiders, and it contains many of the finest pilots and drivers of the Chapter. Kai oversees the war machines of the Grey Knights and the Techmarines that maintain them, ensuring that they remain in perfect fighting condition. If the wards upon a Rhino are imperfect or the engines of a Stormraven less than pristine, it is to Vardan Kai that a battle-brother must answer.2nd Brotherhood ("The Blades of Victory") - Vorth Mordrak commands the 2nd Brotherhood as its Grand Master with Arno Trevan as its brother-captain. Mordrak's brotherhood has a well-deserved reputation for rapid deployment and swift strikes, even by the standards of the Grey Knights. The brotherhood makes use of large numbers of Interceptor and Strike Squads, using mass teleportation and Teleport Homer assault tactics to outmanoeuvre their enemies. The 2nd Brotherhood is often in the vanguard of combined brotherhood assaults, seeding the way for heavier troops to follow. As Admiral of the Fleet, the Grand Master of this brotherhood must possess a skill with manoeuvres that ensures the Grey Knights' rapid deployment to a warzone. Over time, these traits have become synonymous with the 2nd Brotherhood.3rd Brotherhood ("The Wardmakers") - Grand Master Aldrik Voldus, Warden of the Librarium, commands the 3rd Brotherhood with Arvann Stern as its brother-captain. The 3rd Brotherhood has always held a place of honour within the Chapter. It was, according to legend, the first Supreme Grand Master Janus' own brotherhood, and throughout the long history of the Grey Knights it has fostered many of the Chapter's greatest heroes. Kaldor Draigo was brother-captain and then Grand Master of the 3rd, with Arvann Stern following in the current Supreme Grand Master's footsteps. With a reputation for glory, the 3rd Brotherhood has also borne the attentions of some of the Grey Knights' greatest foes. Many times during its history the 3rd has come close to extinction, Daemonic adversaries seeking vengeance for the actions of its brother-captain or Grand Master.4th Brotherhood ("The Prescient Brethren") - Grand Master Drystann Cromm, Keeper of the Augurium, commands the 4th Brotherhood with Ionan Grud as its brother-captain. The 4th Brotherhood contains many of the Chapter's most potent psykers, warriors with an instinctual understanding of the Warp that goes beyond even that of their peers. It is from the 4th Brotherhood that new Prognosticars are often chosen, after they become too badly wounded to fight. The members of this brotherhood has also displayed an uncanny ability to sense danger before it materialises.5th Brotherhood ("The Preservers") - Rothwyr Morvans, Protector of the Sanctum Sanctorum, commands the 5th Brotherhood as its Grand Master with Tauros Hendron as its brother-captain. Some of the greatest heroes of the Grey Knights continue in their duty even after their bodies have been crippled beyond repair, entombed within one of the Chapter's Dreadnoughts. The 5th Brotherhood has long been the warden of the wealth of the Grey Knights' Dreadnoughts, its Grand Master as much the chronicler of their deeds as their commander. While other brotherhoods contain Dreadnoughts, most of these begin within the Sanctum Sanctorum, their histories and glories carefully considered before they are honoured with entombment. Grand Master Morvans is one of the few that speaks with the ancient warriors, often awakening them for war. In battle the 5th Brotherhood will often be deployed alongside several Dreadnoughts, as Morvans is aware that if one of these deathless warriors is left too long dormant he might never be roused. It is a cycle of war that the Dreadnoughts are doomed to repeat endlessly, as long as the Chapter has need of their might.6th Brotherhood ("The Rapiers") - Grand Master Anval Laraon, High Seneschal of the Fortress, commands the 6th Brotherhood with Caddon Varn as its brother-captain. Laraon is an exacting warrior, a trait that saw him ascend to the rank of High Seneschal and is reflected in the warriors of the 6th Brotherhood. The Grand Master believes in no wasted effort or force, often arguing to the Chapter Council against the use of more than a single part of a brotherhood unless the most extreme circumstances call for it. Laraon understands there are far too few Grey Knights for the task of protecting the Imperium, and is loath to waste a single one. The High Seneschal believes that, striking at the right time and in the right place, a handful of Grey Knights can do the job of a whole brotherhood.7th Brotherhood ("The Exactors") - Grand Master Covan Leorac, Representative to the Inquisition, commands the 7th Brotherhood with Darig Tegvar as its brother-captain. The Inquisition and the Grey Knights are inextricably intertwined, their goals often aligning. The 7th Brotherhood has a long history of operations alongside the agents of the Ordo Malleus, and many brother-captains have personal relationships with Inquisitors. As a result, respected Inquisitors are more likely to gain favour from the brotherhood if they call for aid, as more than one Inquisitor has learned. Grand Master Leorac maintains the Chapter's secret knowledge of the Inquisition, tomes of lore on the Inquisitors of each Ordo Majoris reaching back thousands of standard years. It is rare for individual battle-brothers to serve with the same Inquisitor more than once, lest either should learn too much of the other.8th Brotherhood ("The Silver Blades") - Aidan Perdon, Knight Commander of the Recruits, commands the 8th Brotherhood as its Grand Master with Mithrac Tor as its brother-captain. When a newly forged battle-brother joins the ranks of the Grey Knights he will often be sequestered to the 8th Brotherhood. If he proves himself, he may then find a place within one of the other brotherhoods, depending on his natural talents and the favour of the Grand Masters. In time, many of these battle-brothers remain with the 8th Brotherhood, understanding the importance of finding those rare recruits suitable to become Grey Knights and keeping the Chapter alive.