Espandor - Cleansing of Espandor: In early 745.M41, Hive Fleet Behemoth became the first major Tyranid Hive Fleet encountered and defeated by the Imperium of Man. The ensuing conflict became known as the First Tyrannic War. The Hive Fleet was eventually destroyed in late 745.M41 by the combined might of the Ultramarines and White Scars Chapters and the Imperial Navy. Following the events of the First Tyrannic Wars, Espandor's local militia discovered a remnant of Behemoth in the form of a surviving Tyranid nest located deep within the forest.The monsters had been stranded in the Realm of Ultramar after the battles against Hive Fleet Behemoth. The insatiable bioforms had been feeding off the citizens of nearby communities and was rapidly growing stronger every day. At the current rate of growth, the Tyranids would reach a critical mass of population and begin the systematic destruction of the planet. Word soon reached Macragge of the Tyranid creatures attacking settlements on the Cardinal World of Espandor. Chapter Master Marneus Calgar took this as a sign from the Emperor and declared before his assembled Astartes that the newly formed Tyrannic War Veterans would indeed become part of the Ultramarines' military structure. This new infestation would be their first trial and, should they prove successful, then all would recognise their usefulness.During the subsequent Cleansing of Espandor, the Tyrannic War Veterans were organised into three detachments by the Chapter's Reclusiarch Ortan Cassius and together he and First Captain Severus Agemman led them to the site of the most recent Tyranid attack. Having specially modified their Auspexes to detect Tyranid pheromone trails, the Ultramarines were able to track the aliens into the dark depths of the world's primeval forest.The trail continued for many Terran miles, eventually ending at a great, bio-organic structure enmeshed within the trees that resembled a great insect hive. Hissing Tyranid creatures poured from the hive and attacked the Ultramarines, but with Flamers and disciplined Heavy Bolter fire, the aliens were forced back and the warriors of the Ultramarines pursued them within the blasphemous structure.Inside was a warren of caves formed from Tyranid biomass, each tunnel a potential hiding place for a Tyranid bioform. With great discipline, the Ultramarines fought downwards through the hive, cleansing and burning everything before them. At the heart of the hive they discovered a wounded Tyranid that obviously still served as some kind of synapse creature that controlled the lesser beasts. Only its crippling injuries prevented the Tyranids from spreading further across the surface of the planet, but the alien monsters that protected it were no less fierce than any other.The Tyrannic War Veterans fought their way through the creatures and Captain Agemman himself slew the beast. The expertise learned in previous engagements with the Tyranids proved invaluable, as each Astartes knew precisely where to strike their foes to cause maximum damage and understood how the aliens fought. Such was their skill and training that not a single Ultramarines warrior was lost in the battle. With the aliens expunged, the hive and the surrounding area was destroyed by a sustained orbital barrage to ensure that no taint from the aliens survived.