Battle of the Alaxxes Nebula
|Leman Russ leads his Legion into battle against the Alpha Legion|
|Outcome||Strategic Imperial Victory|
Space Wolves escape
| Space Wolves
| Leman Russ
Ogvai Ogvai Helmschrot
| Bulk of Space Wolves Legion
Dark Angels contingent
|Bulk of Alpha Legion|
|Unknown, presumably heavy||Unknown|
While the Space Wolves were still licking their wounds following unexpectedly heavy losses in the Burning of Prospero, the loyalist Legion was ambushed by a sizable Alpha Legion force. The Space Wolves were sent reeling from the attack. Leman Russ organized an immediate retreat, fleeing to the Alaxxes Nebula. The Alpha Legion is able to pursue the Wolves to the Nebula, and the Sons of Russ find themselves completely surrounded and under siege. Russ sends out a distress signal to his nearby brother Primarch Jaghatai Khan of the White Scars, still mostly unaware of the Heresy. After receiving a message from Horus that Russ is in fact the traitor, the Great Khan is skeptical as to who he should side with, particularly after he hears of the Space Wolves razing of Prospero. Jaghatai Khan decides to not aid Russ, instead setting course for Prospero to find out the truth of this civil war for himself.
Realizing his situation is now hopeless, Russ consigns himself to defeat and locks himself in his private chambers aboard the Hrafnkel. During a conversation with Bjorn Russ comes to terms with his past as the Emperor's "Executioner", realizing it has done nothing but brought ruin upon the Space Wolves. First Captain Gunnar Gunnhilt is forced to take command of the Legion, leading a desperate breakout attempt that sees the Wolves facing certain destruction. However at the climax of the battle Russ reappears at the command, moved by the words of Bjorn and pledging to forge his own path from now on and not simply live as the Emperor's Executioner. Reinvigorated, First Captain Gunn sacrifices himself along with his ship Ragnarok in an attempt to destroy the Alpha Legion Battleship Delta and allow for the Wolves' escape. However though the Delta is destroyed, the Alpha Legion are still able to catch up with the fleeing Space Wolves fleet.
A vicious final battle erupts, which sees Leman Russ seemingly battle Alpharius himself disguised as a standard Alpha Legion Terminator. However rescue for the Wolves comes from an unexpected source. A Dark Angels Star Fort Chimaera ostensibly loyal to Luther arrives, having heard Russ' distress signal and determining the Wolves were the true loyalists. With the help of the Dark Angels, the loyalists are able to force the Alpha Legion to withdraw. Victorious, it is revealed that the Dark Angels contingent under Captain Ormand is completely unaware of the events of the Heresy or the crisis erupting on Caliban. Russ informs Ormand and the Dark Angels Chapter Master Althalos the sad news of the Heresy, in exchange for men and material. After hearing the news, the Dark Angels commanders lead their forces back towards Caliban while Russ decides to set course of Terra.