Jericho Reach. A little known galaxy with just a handful of inhabited planets. Until.... From the east of the galaxy a new tendril of the Tyranids, Hive Fleet Dagon, emerged from the cold inky blackness of space. The Imperium detected this invasion into real space and sent their elite division of Space Marines, the Ordo Xenos of the Deathwatch, to investigate and report back on this new invader. Years passed with no response until suddenly a message was received from the planet Credence. The message simply read 'We can control them.' However this message was not only received by the Imperium, the message was scattered amongst the stars by unknown methods and it was heard... From the Imperium the Dark Angels, the Space Wolves, the Flesh Tearers and the Howling Griffons responded to the message. Even an elite group of the Adeptus Custodes arrived in the system. Even the Chaos Gods sent agents to represent them in real space: the Thousand Sons and Daemons of Nurgle.