Predictions and prophecies speak of a rise in Chaos and Warp activity. Ever-watchful for signs of the Arch-Enemy, the Chapter Master of the Imperial Fists has decreed that his Chapter must bolster its strength to counter the upcoming threat. All battle-brothers have been recalled to the Phalanx to re-arm and prepare for the onslaught. New aspirants have been recruited in the hope that a number of them will complete the full transformation into an Astartes to replace losses caused by the upcoming conflicts. The Techmarines and their Servitors aboard Chapter Forge-Ships work ceaselessly to repair damaged wargear and produce new materials of war. The Chapter Ancients are being roused to better aid their Chapter with their extensive wisdom and knowledge in warfare. The Chaplains, deep within the Reclusiam, prepare their sermons and most holy relics. The Librarians steel their minds against the predations of thw Warp, expecting the surge of malefic psychic activity. The line Astartes, each confined for a short time to their hab-cells, reflect upon the upcoming war effort, each Battle-Brother with vows to their Primarch and the Emperor of Mankind upon their lips.
And yet, despite the martial prowess of the Astartes under his command and the great war machines that he has at his disposal, the Chapter Master, ever concious of the Legions of Chaos that lie in wait within the Great Eye, has sent out astropathic hails far out into the galaxy, attempting to reach the ears of the other Chapters who claim to be of the great line of Dorn.
The Crimson Fists, Celestial Lions, Excoriators, Executioners, Subjugators, Iron Knights, and even the renegade Soul Drinkers, have been contacted to send their own Battle-Brothers to fight back their traitorous brethren and corrupted followers.
After many months of preparation, hundreds of fully armoured Battle-Brothers assemble in the Great Hall aboard the Phalanx, before the Chapter Master of the Imperial Fists. The thousand voices all shout the same words, loud and clear, in defiance to the Warp-filth that spills forth from the Immaterium:
"For Dorn and the Emperor!"