Jaghatai Khan - The Path of Heaven: Nearly four Terran years later, the White Scars had successfully waged a guerrilla war against the Traitors' supply lines deep in the void. Though their attacks were devastating initially, over time, the White Scars' numbers were slowly being whittled down to near-critical levels. Following a particularly devastating ambush by the Iron Warriors at Iluvuin, the Khagan was determined to make his way to the Imperial Throneworld, to stand by the Emperor's side when the Warmaster and the Traitors would inevitably invade the Sol System and lay siege to Terra.But they were hindered at every turn -- trapped by the Ruinstorm, the massive Warp Storm conjured by the Word Bearers Traitor Legion during the Calth Atrocity, that blocked off large portions of the Milky Way Galaxy to both interstellar travel and communications. They were also constantly being stalked and harangued by Traitor ships from a combined Traitor taskforce comprised of both the Death Guard and the Emperor's Children, led by Lord Commander Eidolon himself.An opportunity soon presented itself when the White Scars discovered the Kalium Gate, an ancient Warp Gate that dated back to the Dark Age of Technology and had long been abandoned since the Age of Strife. Unfortunately, the White Scars were not able to make use of this Warp Gate, as their tactics and patterns had become predictable to the Traitors, and Lord Commander Eidolon correctly deduced that the White Scars would attempt to utilise the Kalium Gate to reach Terra.By the time the White Scars arrived, they found the Warp Gate was in ruins and that it was teeming with the forces of the enemy. A vicious battle ensued between the two opposing forces. In the ensuing conflict, it appeared that the Khagan had been mortally wounded when he faced the much-changed Lord Commander in battle. But this was merely a feint, as it was actually Keshig Master Qin Xa, wearing the Khagan's armour. Fleeing their attackers aboard the White Scars' flagship Lance of Heaven, Qin Xa would eventually succumb to his wounds.During this time, Arvida could barely hold back back the ravages of the Thousand Sons' mutational Flesh-Change, and each time he utilised his innate psychic abilities, his genetic curse threatened to overwhelm him completely. But before his friend Qin Xa died, he told Arvida to do everything in his power to find a cure for the Flesh-Change. Arvida vowed that he would.It was later revealed that the White Scars presence at the Kalium Gate was merely another diversion, as they had no intention of utilising the Warp Gate, for the Khagan's true purpose was to find the notorious senior Navigator, Novator Pieter Achelieux. Once Novator Achelieux had been found, he led the White Scars to the Catallus Warp rift, where hidden amongst its turbulent Warp eddies was a long, crystalline void station.Within its edifice was an ancient and powerful device known as the Dark Glass, a relic archeotech device from the Age of Technology. Discovered early on by Rogue Traders during the Great Crusade as they opened up new regions of the galaxy for the Imperium, this device was believed to have been used in ancient times to test the technology that would later result in the construction of the Golden Throne. The Dark Glass, like its counterpart on Terra, could access the Webway through the use of a central throne controlled by a psyker of enormous power to operate.Still pursued by the forces of the Death Guard and the Emperor's Children, the White Scars discovered the location of the Dark Glass and intended to use it to instantaneously travel to the Sol System. However, a rogue agent of the Navis Nobilite named Veil, who had accompanied the White Scars, was secretly tasked with the destruction of this archaic device, for it could spell the end of the Navis Nobilite if the technology was widely disseminated across the Imperium.Targutai Yesugai led a small strike force onto the crystalline space station, desperate to make use of the Dark Glass. With the enemy closing in, and the station collapsing all around him due to explosions of Vortex Charges set by Veil, Stormseer Yesugai sacrificed himself by inserting himself into the Dark Glass' command throne and then opened a portal through the Webway to Terra, which allowed the White Scars fleet to swiftly flee through and escape the Traitors' clutches.Before he died, Yesugai's astral form imparted a final message for his friend Arvida -- he asked him to utilise his vast psychic abilities to guide the White Scars' fleet to the Throneworld. As the White Scars' fleet passed through the Immaterium, it was assaulted by hordes of daemons.After he managed to guide the White Scars' fleet closer to Terra, Arvida finally succumbed to the effects of the Flesh-Change and was rendered unconscious. Khalid Hassan, Captain of the Imperial Army's 4th Clandestine Orta and an agent of Malcador the Sigillite, the Regent of Terra, arrived aboard the Lance of Heaven. He promised the White Scars that his master would do everything in his power to treat Arvida's condition, for the Sigillite had long been awaiting his arrival at Terra.In an attempt to save Arvida's life, he was transformed in an arcane ritual conducted by Malcador the Sigillite into an amalgam of Arvida's own psyche and a psychic fragment of the personality of the Primarch Magnus the Red which had been left on the Throneworld after his ritual incursion into the Imperial extension of the Webway. The new hybrid being chose to call himself Ianius, later known to history as Janus, who would go on after the Heresy to become the first Supreme Grand Master of the Grey Knights.