The Battle of Phall was one of the great void-engagements of the Heresy, a duel between two Legions bred for the science of siegecraft. The Imperial Fists fleet, drawn to the edge of the great warp storm, found itself ambushed by the massed vessels of the Iron Warriors, Perturabo's grim legionaries lying in wait to bar their passage.
The hatred between these two brotherhoods was already old and bitter, and it found terrible expression amid the cold dark of the Phall System. Broadsides tore ships apart, torpedoes streaked through the void, and boarding parties clashed in blood-slicked corridors. The Imperial Fists fought not for conquest but for escape, for word had reached them at last that Terra itself lay imperilled and their primarch's place was at the Emperor's side.
Through discipline and desperate courage, the Fists cut their way clear of the Iron Warriors' trap, though at grievous cost in ships and warriors. Phall settled nothing, yet it hardened a rivalry that would burn undimmed through the coming siege. Both Legions would meet again beneath the walls of the Imperial Palace, and there the reckoning begun at Phall would be resumed in earnest.