Grey Knights - Chapter Gene-Seed: The Grey Knights' strength of spirit, indomitable will and purity of mind and body were the most important gifts the Emperor passed on to the Chapter through His unique genetic legacy. Their military training, potent weaponry and powerful armour are simply tools to aid them in their duty.Without the psychic might to use his Nemesis Force Sword or the inviolate will to resist the temptations of the Daemon, a Grey Knight is the same as any other Space Marine -- a potent transhuman soldier in the Emperor's armies but nonetheless a mere shadow of his true potential.The Grey Knights are unique, in that their gene-seed was not descended from any of the original 8 founding Grand Masters of the Grey Knights or the original 20 Space Marine Legions of the First Founding, but from a unique form of gene-seed engineered from the genome of the Emperor of Mankind Himself -- what is known as the "Emperor's Gift."Few warriors since the Horus Heresy have matched the flawlessness of the Grey Knights, nor are any so closely linked to the Emperor. It is that unique quality that the Emperor possesses, the nature of His spirit and mind that allows Him to touch the Immaterium, shape it to His will, and yet remain beyond its madness and corruption, that He has gifted to the Grey Knights.Even the Space Marines of the Adeptus Astartes are genetically too far removed from their creator to embody such psychic and moral purity, their genetic integrity faded by hundreds of generations and thousands of Terran years, given to varying degrees of imperfection and even mutation. Not so the Grey Knights, whose unblemished line reaches back to their maker in an unbroken chain. Only an unblemished soul is proof against the spiritual assault of Chaos, and of all the servants of the Emperor the Grey Knights are among the rare few to be all but immune.Each Grey Knight is a one in a billion example of Humanity that has an instinctual command of his psychic powers, the rarest of genetic traits that, when combined with the unusually potent gene-seed of the Grey Knights, grows into a formidable and exceptional tool to combat Daemons.Without these gifts a mortal might become a plaything for the powers of the Warp, their physical body twisted into vile and terrible new mutant forms or their psyche ripped asunder by vile Daemonic thoughts and visions.As the Imperium learned to its sorrow during the Horus Heresy, the Warp can corrupt even a Space Marine, the lies of the Chaos Gods subverting his martial pride or loyalty to the Emperor into a dark and dangerous thing.Power armour and bolt rounds can protect neither mortal man nor Astartes from the spiritual temptations of the Immaterium, should they be exposed to its baleful energies. The Emperor alone was said to be incorruptible before the temptations of the Dark Gods, and it is this gift He was rumoured to have passed on to the Grey Knights.Certainly, despite countless battles against Daemonic forces and in the hundred centuries since their creation, not a single Grey Knight has succumbed to the influence of the Ruinous Powers -- a testament to the skill of their creator and the dedication to Humanity they embody.