List of Space Marine Chapters - G: NameOriginFoundingNotesGenesis ChapterUltramarinesSecond FoundingThe Genesis Chapter is a Second Founding Successor or Primogenitor Space Marines Chapter of the legendary Ultramarines. The Chapter's homeworld is the planet Newfound which is located a comparatively short distance to the galactic northwest of the Ultramarines' Realm of Ultramar. First amongst the Ultramarines' Primogenitor Chapters to be raised (and hence their name), the Genesis Chapter is dogmatically loyal to the Imperium of Man and the memory of its Primarch Roboute Guilliman.Golden BladesUnknownUnknownThe Golden Blades was a Loyalist Space Marine Chapter of unknown Founding and origin. Sometime in the 37th Millennium, a garrison of Golden Blades Space Marines met a most foul fate while defending the world of Ghahalla during a daemonic incursion. Overcome by a strange madness, they slowly succumbed to their madness and were reborn as the first seeds that would become the Khorne Daemonkin warband known as the Brazen Beasts.Golden GryphonsUnknownUnknownThe Golden Gryphons is a Loyalist Codex Astartes-compliant Chapter of Space Marines of unknown Founding and origin.Golden HalosUnknownUnknownThe Golden Halos is a Loyalist Space Marine Chapter of unknown Founding and origin.Golden PaladinsUnknownUnknownThe Golden Paladins is a Loyalist Space Marine Chapter of unknown Founding and origin. The Chapter's homeworld of Lynoxis fell to the 7th Plague Company of the Death Guard Traitor Legion, led by the Daemon Primarch Mortarion himself, after the birth of the Great Rift.Golden SonsBlood AngelsUnknownThe Golden Sons is a now-extinct Successor Chapter of the Blood Angels, created during an unknown Founding. It was known for taking a much harsher stance for those battle-brothers afflicted by the Black Rage, as it hurled its Death Company into battle with no concern for their lives. The Golden Sons were fatally undone by the genetic curse of the Black Rage.Gore GolemsUnknownUnknownThe Gore Golems are a Loyalist Space Marine Chapter of unknown genetic origin and Founding.GorgonsUnknownUnknownThe Gorgons is a Loyalist Chapter of Codex Astartes-compliant Space Marines of unknown Founding and origin.Graven FistsUnknownUnknownThis Chapter undertook the disastrous Abyssal Crusade in 321.M37 into the Eye of Terror, where it was corrupted by Chaos, and became the warband of Chaos Space Marines known as the Twisted Blades. Declared Excommunicate Traitoris.Graven SpectresUnknownUnknownThe Graven Spectres was a formerly Loyalist Space Marine Chapter of unknown Founding and origin. In 365.M41, the Renegade Chapter assaulted the relic world of Syban, intent on plundering its great stasis museum. During its rampage it unwittingly released the Daemon Prince Knor from his millennia-long slumber.Grey GiantsUnknownUnknownThe Grey Giants is a Loyalist Space Marine Chapter of unknown origin and Founding.Grey KnightsEmperor of MankindUnknownThe Grey Knights is a secret, mysterious Loyalist Chapter of Space Marines specifically tasked with combating the dangerous daemonic entities of the Warp and all those who wield the corrupt power of the Chaos Gods. It has the honour of being implanted with gene-seed engineered directly from the genome of the Emperor Himself. The Grey Knights act as the military arm or Chamber Militant of the Ordo Malleus, the Daemonhunters who form the oldest branch of the virtually omnipotent Inquisition. Unlike other Astartes, every Grey Knight is a potent psyker.Grey SlayersUnknownUnknownThe Grey Slayers is a Loyalist Space Marines Chapter of unknown origin and Founding that became corrupted by Chaos. Inquisitor Thrax purged the Chapter of mutants and daemons, and the Chapter Master took his own life in shame. Untainted officers were raised up to lead the Chapter. The purge was apparently not quite thorough enough, as Inquisitor Thrax himself was soon afterwards corrupted by the Ruinous Powers and transformed into some sort of daemonic Chaos beast. The Grey Slayers' eventual disposition and fate remains unknown in current Imperial records.Grief BringersUnknownUnknownThe Grief Bringers is a Loyalist Space Marine Chapter of unknown origin and Founding that suffered heavy losses fighting against the Warp entities called Enslavers on the world of Valhall II. Its armour is described as "principally a sickly pea-green, with engrailed chevrons of headachey purple."Griffon LordsUnknownUnknownThe Griffon Lords is a Loyalist Space Marine Chapter of unknown Founding and uncertain origin. This Chapter is a rare example where its Astartes' beliefs are in conflict with official Administratum records, as they claim to be descended from the Ultramarines' Primarch Roboute Guilliman, even though official data-files show that their ancestry is that of Jaghatai Khan's White Scars.Guardians of CeleresUnknownUnknownThe Guardians of Celeres is a Loyalist Codex Astartes-compliant Space Marine Chapter of unknown Founding and origin.Guardians of the CovenantDark AngelsUnknownThe Guardians of the Covenant is a Successor Chapter of the Dark Angels, of an unknown Founding. This Chapter is as dedicated to the scholarly arts as to the ways of war. Masters of both, the battle-brothers of this Chapter use their keen intellects as a weapon as sharp as their Chainswords. The Chapter's Astartes study the teachings of the Emperor and of their Primarch Lion El'Jonson in minute detail, attaining a unique perspective on the object of their diligent studies. Every shred of ancient wisdom is absorbed, debated and analysed, so that no ruse or stratagem is beyond the Guardians of the Covenant, and none may better them on the field of battle.