Fidus Kryptman - Battle of Macragge: Thanks to Inquisitor Kryptman's discoveries at Tyran Primus, the defenders of Macragge had been forewarned of the horror headed towards them. Upon learning of the threat posed to Ultramar by Hive Fleet Behemoth, Marneus Calgar at once drew up his plans. Deeming Macragge to be the star system most immediately threatened, Calgar ordered its already formidable defences to be further improved.A dozen Imperial warships already hung in orbit, and each day more arrived from the Warp. Massive Strike Cruisers cast shadows over civilian vessels and Imperial Navy Destroyers, and were themselves dwarfed by the brooding presence of the Ultramarines' Battle Barges. Between this mighty fleet of warships and the planet's no less formidable orbital defence stations, Macragge was anything but defenceless.As the Ultramarines readied themselves for all-out war with the Tyranids, Kryptman allowed himself a glimmer of hope. He heard the news that the Imperial Navy's Battlefleet Tempestus had finally been dispatched from the orbital docks at Bakka. Kryptman had met with Marneus Calgar, and after long discussion agreed that Macragge was the star system most immediately threatened by Hive Fleet Behemoth.A solar month later, the Tyranids attacked Macragge, and a fleet of bio-ships now numbering well over 1,000 vessels swept aside attacks by those Ultramarines' Strike Cruisers defending the outlying worlds as they pushed in-system. A large section of the Tyranid fleet then descended upon the Garden World of Prandium, a paradise once referred to as the jewel in Ultramar's crown, and left a barren ruin in its wake. Despite the Inquisitor's warnings, Calgar was shocked to the core by the fate of Prandium.After Hive Fleet Behemoth was finally destroyed after the sacrifice of an Imperial Battleship created a Warp vortex that destroyed the majority of the Hive Fleet, Calgar's surviving starships came about and roared back to Macragge to try to save the beleaguered polar garrisons of Ultramarines, who had been engaged against the Tyranids for days while the Imperial fleet engaged the Great Devourer in the void. Calgar, feeling that the situation was becoming critical, sent the 3rd and 7th Ultramarines Companies ahead in their fast Strike Cruisers while his remaining damaged warships limped back to Macragge.Despite horrendous losses inflicted upon the Tyranid fleet from Macragge's orbital and polar defence grids, many Tyranid organisms were able to reach the surface of the planet. The Tyranid swarm swept across the planet with the most intense fighting in the region of the northern polar defence installations. Though the Ultramarines fleet was able to destroy the Tyranid bio-ships, horrific casualties were suffered by the planet's population as well as the Chapter.Calgar went down to the planet's surface, leading the 3rd Company against the ravenous hordes of the Great Devourer. The entirety of the elite 1st Company was wiped out to a man whilst defending the northern pole's defence grid. The Ultramarines 1st Company was gone and the 3rd and 7th sorely diminished. It would be many long years before the Chapter could properly replace its losses from the Battle of Macragge, but replace them it would.