Battle of Trisolian
|Horus and Leman Russ battle aboard the Vengeful Spirit|
|Outcome||Space Wolves retreat, Horus wounded by the Spear of Russ|
| Leman Russ(WIA)
Ogvai Ogvai Helmschrot
Hester Aspertia Sigma-Sigma(KIA)
| Near entirety of Space Wolves Legion
| ~50 capital ships from the Sons of Horus, Word Bearers, Alpha Legion, World Eaters, Night Lords, and Iron Warriors|
Traitor Imperial Army
|Extremely heavy, several Great Companies losing 4/5th of their strength||Moderate to heavy|
The Battle of Trisolian, also known as the Wolf Cull, was a battle during the Horus Heresy.
The battle began as a minor Traitor occupation of the Trisolian System, Mechanicum territory previously affiliated with the Emperor. A small armada of Horus' main fleet, led by the Vengeful Spirit itself, dispatched a force of Night Lords to overrun much of Trisolian A-4. Though the loyalist Mechanicum Thallax and Myrmidon Destructor cohorts were prevailing, the commanding Magos Domina, Hester Aspertia Sigma-Sigma, ordered a surrender and had her units stand down. Despite protests from her acolyte Belisarius Cawl, Aspertia calculated that while they were currently winning the battle they were ultimately doomed. Sota-Nul, accompanied by Horus himself, arrived on the planet shortly after to receive the surrender of the loyalist Mechanicum. Most of the Tech-Priests surrendered and pledged themselves to Horus, and those who did not were executed. Cawl was spared by Aspertia, who valued her expertise.
Meanwhile, Leman Russ had left Terra on a mission to hinder Horus as he drove towards humanity's throneworld. Thanks to the efforts of the Knights-Errant during the Battle of Molech, the Space Wolves could track the location of the Vengeful Spirit at all times thanks to hidden runes aboard the traitor vessel. After a stop at Fenris to conduct an archaic ritual where Russ learned the truth regarding the Spear of Russ and the very nature of his existence, the Wolf King enthusiastically announced his desire to make his move on Horus. As Russ knew victory was hopeless and the best he could hope to do was "wound" Horus, he let the mission be voluntarily among his Wolf Lords. None of the Space Wolves refused to follow their Primarch to the death that awaited.
As Horus' escort fleet of around fifty capital ships from various traitor Legions hung in orbit over Trisolian 4A, the Space Wolves struck. Using the gravity well and solar radiation between two of the Trisolian System's stars, the Space Wolves both hid their presence and accelerated to great speed. They suddenly appeared on top of the traitor fleet, and a vicious duel erupted between the two armadas. All of these battles were but a distraction, as Russ had his flagship Hrafnkel engage the Vengeful Spirit at point blank range. Before the Void Shields of the Vengeful Spirit were even disabled, a massive boarding operation led by Russ personally was launched from the Hrafnkel, consisting of Boarding Torpedoes, gunships, and Assault Boats. The Vengeful Spirits shields dropped thanks to heavy fire from the Hrafnkel just as the boarding force slammed into the vessel, unleashing thousands of Space Wolves into the interior of the vessel. Russ himself landed in a hangar of the Vengeful Spirit aboard his personal Stormbird Hugin.
A vicious battle in the interior of the vessel erupted, as boarding parties led by Russ, Bjorn, and Bror Tyrfingr swarmed the now-corrupted Vengeful Spirit. Encountering not only traitor Astartes but also Human soldiers, corrupted Skitarii, and Possessed, the Space Wolves managed to fight their way into the heart of the vessel while taking heavy losses. Parts of the corrupted ship responded to their presence, rearranging its halls to separate and confound the Wolves. Meanwhile, thanks to the efforts of Belisarius Cawl, the treacherous Magos Domina Aspertia was eliminated, and her forces reverted back to loyalist command and aided the Space Wolves.
At last, Russ and his Wolf Guard were confronted by Horus and his Justaerin. The Warmaster oozed daemonic corruption since the events of Molech, and Russ was disgusted by what had become of his brother. Nonetheless Horus pleaded with Russ to join him and help in his quest to overthrow the Emperor and expose his lies. Surprising none, Russ rejected Horus and the two engaged in a titanic battle. Despite Horus' sorcerous powers, Russ was protected thanks to the Spear of Russ he wielded. It thus came down to a battle of sheer power, one Horus was dominating despite Russ' speed. Horus caught Russ upon his Talon, but Russ broke free of his armor and impaled flesh to plunge the Spear of Russ into the Warmaster's side. However Russ hesitated at the final second to deliver the killing blow, and instead only partially pierced Horus' side. The wound was still devastating, and more importantly the power of the Spear cleansed Horus of the corruption that had befallen him since Molech. For the first time in the battle, Russ saw Horus Lupercal before him, not a creature of Chaos.
Despite the effects of the Spear, Horus still remained committed to the Emperor's destruction and rejected Russ' offer to return to Terra and allow the Emperor to heal him. The two Primarch's again came to blows, and this time Russ was badly mauled by Horus' talon. As Horus stood over Russ and was about to deliver the final blow with Worldbreaker, a single Space Wolf rushed to his Primarch's aid and was swatted aside by Horus. Soon more came, and then hundreds, until Horus was swarmed by a desperate mob of Space Wolves piling upon him. The distraction gave Bjorn and Russ' Wolf Guard captain Grimnir Blackblood enough time to drag the barely-conscious Russ away from the battle as Horus massacred those that stood in his path. Meanwhile within the bowels of the Vengeful Spirit, Bror Tyrfingr's squad was wiped out by Abaddon and his Justaerin retinue.
With Russ near death, Grimnir Blackblood took command and ordered a general retreat. The Wolves fled the Vengeful Spirit with Horus at their heels, with Bjorn only able to drag Russ back to his Stormbird thanks to the sacrifice of Blackblood himself. Bjorn and Russ made it back to the Hrafnkel, and as the Vengeful Spirit closed in to finish the vessel one of its magazines exploded, crippling the ship and allowing the Space Wolves time to escape. The Space Wolves managed to narrowly escape, but were horrifically mauled and their casualties in many places were below 1/5th of their original strength. The Wolves essentially ceased existing as a Legion as a result of the battle.
Horus, though victorious, felt hollow from what the spear had done to him and the fact that Russ could have slain him had he not hesitated. He nonetheless ordered that his fleet push to Beta-Garmon, while dispatching Abaddon to pursue the remaining Wolves. Months after Trisolian, Horus fell into a coma on Beta-Garmon as the wound Russ gave him reopened and the Chaos Gods fought over his doubt-plagued soul. In the end, it took the sacrifice of Maloghurst to restore the Warmaster.