Under the command of Horus Lupercali (who is suffering from nightmares/memories of the Lupercal), the Imperium engages in a multi-prong offense into the Golgotha Wastes. Horus and Tengri pushing towards Ullanor and their five brothers each tearing into the Wastes to distract the "Biggest of da Beasts.'' The eight most powerful Orks in Golgotha., who are:
Urg Mag Uruk Thraka- Beast of Beasts. Ten Meters of unstoppable Orkish killing power.
Zahubu-Ura-Gog- Beast Prophet. Slain by Tengri.
Urlakk Grond- Fastist Beast, pioneered the use of Rokket Ships and the Mork Tunnels.
Maga da Zapboss. - Mek Beast, and chief Wattboss
Gharkul Blackfang- Ancient and unpleasant Beast that remembers the Golden Age of Humanity.
Snaggit Secretkeepa- An incredibly clever Grot that acts as the Spymaster Beast.
Bagorr Da Trash Heap Terror- Insane and disturbingly intelligent scavenger Ork Beast,
Da Warp Spewa- Pyromanical Wyrdboy Beast capable of psychic destruction
Horus uses the memories taken from Lupercal to easily outmaneuver and fight the Orks. While he is afraid of the potential dangers of them and has some very very dark recollections from Molech, Horus starts to recover from the trauma of dying with help from Uriah. Things dramatically turn for the worse when the Orks start using primitive pseudo-Webway gates called Mork Tunnels (As seen in WAAAGH!!! Beast) The sudden mobility advantage blindsides the Imperium and Orkish fleets start appearing in Imperial space. Alexio and Rogal put a stop to the raids but not ever much damage is done.
The sudden development of this tech raises questions and the Emperor sends a team to investigate while he and the Custodes join the push to Ullanor. Arik Taranis and some Order Metallic Agents learn that the Harlequin are aiding the Orks and guiding them towards becoming Krork on the direction of Cegorach. This prompts a desperate attack by the Imperium to crush the Orks before the Old One's influence becomes too much. The Emperor, Horus, Vulkan, and Tengri, accompanied by their Legions, made a daring strike against Ullanor. Punching through the Orkish defenses using the Bucephalus and Ayida the Stellar Dragon as a spear point. At Ullanor, Horus, Vulkan and Tengri face down Urg Mag Uruk Thraka, and his lieutenants. While the Emperor embarked on another more secret mission to collect a treasure of the Old Ones hidden in the Orkish capital world.
The battle is fierce and Tengri has both his eyes ripped out by Urg Mag Uruk Thraka. While Vulkan dies a dozen deaths holding back the other Beast Bosses while Horus and Tengri strike down Urg Mag Uruk Thraka. The Vth Primarch will eventually heal but spends much of the Ullanor battle a blind hurricane of whirling blades. The Imperium wins the battle and the Orks break. The other four Legions are ready to begin the slaughter. Billions of Orks die and the stars run red with Greenskin blood. But a not-insignificant chunk of the Golgothan Empire breaks through the Imperial cordon and flees towards the galactic South-East, called by some unknown power.
Meanwhile, the Emperor gains the final pieces he needs to assemble a Soul Engine, a Psychic tool invented by the Old One that lets a sufficiently powerful Psyker warp Space/time using the Warp/Souls to alter the fundamental fabric of reality. With this victory, the Emperor leaves for the far Galactic north to help fight the Rangda. The seven Legions assembled to fight the Orks disperse and continue to conquer the galaxy in the Emperor's name.