From the preview:
In the unending war for the Antian Sector you have battled plague-bearing daemons and warbands of feral Orks, tainted Imperial bureaucrats and the Striking Scorpions of the Eldar. Now, the Halls of Terra expansion for Relic takes you on a mission to the sacred birthplace of humanity to garner the support you need to save untold billions of human lives.
Yet enemies to mankind thrive even in the ancient heart of the Imperium, and the Chaos emanating from the Antian Sector’s Warp Rift spawns heresy and corruption throughout the galaxy. In Halls of Terra, a new orange Threat deck brings to life the obstacles you may encounter on Mars and Terra, from ruthless Inquisitors to painful ritual purifications. Today’s preview introduces the perils of this Threat deck, along with two new scenarios in which Chaos and corruption spread beyond the Antian Sector, endangering the Sol System and your character’s soul.