Ultramarines - Battle of Thessala: In 121.M31 during the final days of the Great Scouring, Roboute Guilliman assembled the Ultramarines and six of its Successor Chapters to hunt down the Daemon Primarch Fulgrim and his Emperor's Children Legion once and for all. At the world of Thessala, Fulgrim laid a trap for the Ultramarines' fleet and nearly turned the tables on his hunter.Guilliman gathered a small, elite strike force and teleported aboard the Emperor's Children flagship Pride of the Emperor to put an end to the Daemon Primarch. Guilliman entered the great ship's corrupted Heliopolis alone, where he was soon confronted by Fulgrim, who tried to convince Guilliman to embrace the worship of the Chaos Gods like he had.Guilliman refused and the two primarchs clashed, but it was soon obvious that Guilliman was no match for Fulgrim's Warp-enhanced strength and sinuous new Daemonic form. Seeing that he was about to be slain by his brother, Guilliman called for aid from his Ultramarines, but as their forces entered the Heliopolis, Fulgrim called forth a horde of Emperor's Children who had been waiting nearby as well.As their gene-sons fought around them, the two primarchs clashed once again, but Fulgrim proved victorious when he slit Guilliman's throat with his poisoned sword. A shocked Guilliman asked Fulgrim how he was able to fatally wound him and Fulgrim replied that his Warp infused eyes had seen the scar Kor Phaeron's athame had inflicted upon Guilliman during the Battle of Calth.Guilliman collapsed unconscious, but was teleported back to safety aboard the Ultramarine flagship Gauntlet of Power, along with the surviving Ultramarines of the 1st and 2nd Companies that had accompanied him. He was placed in a stasis field for return to Macragge. Afterwards, the Emperor's Children massacred Guilliman's fleet. The Gauntlet of Power was among the few Loyalist warships that escaped the slaughter.Once on Macragge, the Shrine of the Primarch built to contain Guilliman's body frozen in time was one of the most holy places in the entire Imperium, and one which welcomed millions of pilgrims to the shores of Macragge every Terran year in the days before the primarch's resurrection.The Shrine of the Primarch lay within the Temple of Correction, a vaulted sepulchre forming a small part of the Ultramarines' vast northern polar fortress on Macragge. The temple is a miracle of construction and typical of the attention to detail which defines the Ultramarines' every endeavour. Its proportions defy the Human mind by the scope and grandeur of its design.The multi-coloured glass dome that forms its roof is the largest of its kind. Even the Techno-magi of the Adeptus Mechanicus come to marvel at the structure said to have been designed by Roboute Guilliman himself. According to the Ultramarines there is enough marble within the temple to build a mountain, and sufficient amounts of adamantium and plasteel were used in its construction to build an Imperial warfleet capable of defending an entire sector.Within this edifice was the great marble throne of Roboute Guilliman, and upon that throne sat his still-regal body. Though 10,000 standard years passed following the Battle of Thessala, the primarch's body was perfectly preserved by the stasis field. Even his death wounds from Fulgrim's blade remained visible upon his throat.His mortal remains were preserved from the ravages of time by a stasis field that isolated the primarch from the passage of normal, four-dimensional space-time. Everything encompassed by the field was trapped in time and could neither change nor decay.There were some among the more extreme devotees of the Imperial Cult, however, who claimed the primarch's wounds in those years did change. They claimed that Guilliman's body was slowly recovering and that his wounds showed mysterious signs of healing. Others denied this, and pointed out the sheer scientific impossibility of any form of change occurring within a stasis field.Yet enough chose to believe the stories to come and witness for themselves the supposed miracle of the primarch, generation after generation. Hope, as Roboute Guilliman well knew, is truly the most powerful force in the universe.