A group of Space Marines of the Imperial Fists Chapter come under attack. A Space Marine by the name of Nidon is told to protect "the codex", and at that very moment a fireball engulfs the Astartes. Brother Proteus (Sean Pertwee) and Captain Severus (Terence Stamp) of the Ultramarines Chapter are locked in close combat onboard a Space Marine Strike Cruiser. As the other members of Ultima Squad watch, Proteus manages to disarm Severus and demands his surrender; however, Severus escapes Proteus' grasp and in turn defeats him, declaring that a Space Marine never yields. Afterwards the members of Ultima Squad are shown a sacred weapon of the Ultramarines, a relic Thunder Hammer, the Hammer of Macragge, that lies in their ship's Reclusium. The captain and the Apothecary Pythol (Donald Sumpter)