The Horus Heresy: Tallarn: Executioner

As one of the many staging grounds for the forces serving in the Great Crusade, the verdant world of Tallarn has long served as a transfer point for the personnel and war machines of the Imperial Army. Now, destroyed by a deadly virus-bomb attack launched by the battered Iron Warriors fleet, the entire world is reduced to a toxic wasteland where the survivors must fight to defend what little remains of their home. The remnants of the once mighty Jurnian 701st armoured regiment emerge from their underground shelters, and the opening movements of the Battle of Tallarn begin... even as more clandestine powers seek to manipulate events on both sides of the conflict.