Editing Battle of Calth (section)

==Prior to the battle==
After [[God-Emperor of Mankind|Big E.]] chastised and publicly shamed the [[Word Bearers]] by making them kneel in front of him and the [[Ultramarines]], [[Lorgar]] was [[butthurt|slightly miffed]], fell to [[Chaos]], started the [[Horus Heresy]]... you know the drill.

Horus ordered the Ultramarines to muster at Calth, ostensibly for a joint operation with the Word Bearers against some [[Orks]]. Because of his distance from the galactic center and the general absence of reliable communications in the Imperium, Guilliman had no idea that the [[Drop Site Massacre]] had happened or any inkling that anything was wrong at all. From his point of view there was nothing to suspect and he hoped that this action would mend his relationship with his brother, so he assembled (almost) all of his Legion at Calth and waited for Lorgar's troops to arrive.

On Lorgar's part, he and his brother [[Angron]] got together in the aftermath of the [[Battle of Isstvan III|battles]] at [[Drop Site Massacre|Isstvan]], collected three hundred thousand legionaries between them and double-timed it to the Ultramar sector, initiating the '''Shadow Crusade''' on the way and burning a ''"bloody trail across the eastern segmentum"''. The Ultramarines were ignorant of these early battles thanks to both the speed of the traitors' advance and the fact that they seldom left any survivors.

When preparing for the muster at Calth, Lorgar split his Legion into multiple groups. He kept the larger part for himself, but deployed 50,000 Marines chosen from the most unstable and least zealous elements of his legion to represent him in the hopes that they would be killed off. He also gave them the bulk of his fleet to maintain the ruse that the entire legion had arrived at the muster, when in fact they were already spread throughout the 500 Worlds causing generalized mayhem.

While Lorgar desired to get back at Guilliman, he had been informed through the counsel of [[Kairos Fateweaver]] (and it should be noted that this is still the ''only'' time both of its heads were compelled to speak the truth) that the upcoming battle would have been his opportunity to kill Guilliman if he wished, but if he did so it would actually hinder the traitors' efforts to reach Terra and potentially cause Horus to fail in the long run. We now know with hindsight that if Guilliman had died then the [[Imperium Secundus]] would not have happened and the resources and manpower that he gathered to support his backup Imperium would have been spread elsewhere. Therefore while Lorgar was present at the muster at Calth, he departed to continue the Shadow Crusade as soon as the battle started, leaving overall command to [[Kor Phaeron]].