Roboute Guilliman - Imperium Secundus: As a result of being cut off from access to Terra and much of the rest of the galaxy by the vast Warp Storm called the Ruinstorm that was created by the treacherous Word Bearers at the Battle of Calth, Guilliman feared that the great dream of Human unity was in danger.With no way of knowing whether Terra was under assault or the Emperor was even still alive, Guilliman moved to safeguard the ideals of the Great Crusade and the Emperor by creating a second Human interstellar empire, the Imperium Secundus, as a contingency. It was an action he would later consider one of his greatest blunders.Many Loyalist Space Marines trapped behind the line of the Ruinstorm were brought to Macragge thanks to the activation of the ancient xenos device located on the Ultramarran world of Sotha known as the Pharos, which functioned much like the now-obscured Astronomican as a beacon in the Warp.Guided by the Pharos' beacon, many Loyalist warships of the Shattered Legions and other Loyalist forces were able to make their way through the Immaterium to the Ultramarines' homeworld.Not wanting to appear vain and power-hungry like his brother Horus, Guilliman refused to declare himself the Emperor of Imperium Secundus, instead initially trying to convince his fellow Primarch Lion El'Jonson, who had arrived at Macragge with his Dark Angels Legion, to take the position despite being distrustful of El'Jonson's motives.While organising the creation of Imperium Secundus, Guilliman survived an assassination attempt by an Alpha Legion squad disguised as Aeonid Thiel and other Ultramarines. Later, when the Night Lords Primarch Konrad Curze, who had secretly taken refuge on the Dark Angels' flagship was let loose upon Macragge, Guilliman and the Lion battled the Night Lords primarch together but were led into a trap by the Night Haunter.Instead of being cornered, Curze detonated charges and brought the entire structure into which the other primarchs had been lured down upon their heads. Guilliman and the Lion survived thanks only to the Loyalist Iron Warrior Barabas Dantioch activating the Pharos, which teleported the pair to Sotha.El'Jonson and Guilliman then made their way back to Macragge, where the Blood Angels Legion had recently arrived in the wake of the horrors of the Signus Campaign. Guilliman decided to name the reluctant Sanguinius the Regent of Imperium Secundus, so none would hold the title of "Emperor."However, in the short history of the existence of Imperium Secundus, Guilliman frequently clashed with his distrustful and taciturn brother Lion El'Jonson over policy. Obsessed with hunting for Konrad Curze on Macragge, the Lion insisted that the Night Haunter was behind the rebellions which began to plague the Ultramarine homeworld and he demanded that martial law be instituted, which Guilliman strongly resisted.After a suicide bombing struck an Astartes convoy on Macragge, the Dark Angels were deployed by the Lion to establish martial law without Guilliman's express permission.Guilliman and El'Jonson again disagreed over the rebellion that had broke out in the Illyrium region of Macragge, with the Dark Angels primarch wishing to unleash weapons of mass destruction in an attempt to flush the rebels out as he suspected Curze was hiding in the region.When Guilliman again objected to such an indicriminate use of force that would take much innocent life, the Lion instead commanded a more conventional Space Marine assault on Illyrium, and Curze was finally captured. Again at Guilliman's insistence, the Night Haunter was given a public trial to account for his treason.During the trial, Curze revealed that Lion El'Jonson had ordered secret orbital strikes against the Illyrian rebellion in express contravention of Guilliman's wishes. This revelation enraged the Dark Angels primarch and nearly led him to kill Curze in the midst of the trial.Angered by their brother's duplicity and consistent disregard for Imperial principles, Guilliman and Sanguinius dismissed and ordered El'Jonson and the Dark Angels to leave Imperium Secundus, but repenting of his actions, the Lion later requested that he become Curze's jailer instead, as the Night Haunter's life had been spared.