Damocles Gulf Crusade, 745.M41. The Imperium and the Tau are at war, as the Imperium tries to stamp out the unrest caused by the Tau forces, and the Tau try to take their place in the galaxy.
In the Imperium-controlled system of Tiskar, on the edge of the Tau Empire territory, the Tau and the Imperium are fighting over the rich mineral deposits on the planets and asteroid belts in the system. A Necron tomb world begins to awaken from a small moon in the system, previously mined to its ultra dense and impenetrable core. Utterly riddled with caverns and warrens, it is a haven for pirates and malcontents, but little do they know what lies beneath their feet. On many of the system's planets, an ancient city is discovered, buried under eons of rubble, runes of unknown origin decorate the structures. It appears as if the Imperial Eagle decorates these structures, but anyone who tries to discuss these events disappears mysteriously, and the ruins quickly fade into obscurity. When the ruins were discovered, a warp rift opened on the edge of the system. Disgorging hordes of Chaos forces, the warp rift shuts as mysteriously as it opened, but not before a space hulk crashes its way into the material universe, brimming with Orks. On the planets, rumors start to spread of corruption in the human noble classes. A fractured nobility presides over the system, with some converting to the Greater Good, some practicing more...barbarous faiths, while most yet cling to the God-Emperor of Mankind. They have all noticed, however, a final few are found dead from a sniper's bullet. Meanwhile, the astropaths notice that the warp grows dark with menace, a blackness that creeps closer and closer. One final message is sent, destined for those who may heed its call, then a warp storm encloses the system. It is a dangerous time to try to eke out a living in this sector of space...
----INQUISITORIAL DISPATCH----
Lord Inquisitor Khan of the Ordo Xenos, to the Grand Inquisitor of the Ordo Xenos
My Lord, the Damocles Gulf Crusade is in progress. Forces are allying together against the Imperium, as the Tau attempt to take what is not rightfully theirs. Messages have been sent to all available forces, for runes that have been found are believed to have been from M30, from the time of the Horus Heresy. I fully expect to see Excommunicate Traitoris Legions appear within the following weeks. I request that you to forward this to those in Ordo Malleus and Hereticus who may be concerned, as I do not have the resources to deal with this. I was prepared to deal with the Tau, but the extra forces arrayed against us will be a problem. We will begin corrective actions against the foes of the Imperium, but I have my doubts. This is a vital source of adamantium and promethium, and also hosts a known warp route. I have fully deployed my Scions and the assassins available to me, and I believe some of the Adeptus Astartes will aid us. It will not be enough. Send support.
We are one with the Emperor, our souls are joined in his will.
Selius Khan