The physical attributes of the Adeptus Astartes made them formidable warriors. Their size, speed, weapons and armour made each of them a fighter capable of taking on the worst that xenos and heretics could bring to battle. Psychodoctrination made them fearless. Training and deep learning had turned every Primaris Marine into a tactical expert, able to take up a leadership position should a sergeant fall. Their vox-network, auspexes and other armour systems gave them unparalleled coordination among the soldiers of the Emperor, both between individuals and squads, and all the way up to entire companies of warplate-clad transhumans.

All of this combined to give Nem­etus and his Ultramarines the most important quality: absolute trust. If a battle-brother said he would guard a junction, he knew that Space Marine would guard the junction until dead or relieved, no matter what happened. If a gunship pilot asserted that he would be at the extraction point in precisely ninety-four seconds, then Nem­etus would know that the pilot would be there if it was possible.

It also meant that when Praxa­medes had told him that he had identified a weakness in the dorsal hull of the cruiser, and could crack it open with a single bombardment cannon shot no more than forty yards from Nem­etus’ current position…

Even so, it was some effort to concentrate on the ongoing firefight that embroiled the halls and corridors on the deck three levels above the strategium. The thought of the broad gun atop the spine of the Ithraca’s Vengeance turning to bear upon a cracked slab of ferrocrete not far above his head was an image Nem­etus could not wholly push away as he slashed his blade through the padded jerkin and chest of a young traitor crewman.

‘Enemy forces incoming from aft,’ warned Dorium. ‘Six or seven hundred life signs. Two hundred yards.’

Nem­etus did not need an auspex to picture the situation, his mental image updated to bring in a fresh tide of humans and mutants. He used his shield to slam aside another foe, skull crushed as it flopped to the floor.

‘Acknowledged, brother-sergeant. Complete final withdrawal to defensive perimeter.’

A green flash of light bounced from his pauldron and the lieutenant turned, confronting a grey-haired woman with a laspistol held in both hands. She shrieked something in a language he didn’t understand, eyes filled with hate. He caught the next flurry of las-blasts on his shield a moment before a bolt from one of his companions punctured the woman’s chest and then exploded, cutting her almost in half.