From the Introduction: Hail all loyal Tech-Priests and other servants of the Machine Cult! Welcome to The Lost Dataslate, a compilation of additional material for The Lathe Worlds, the Dark Heresy supplement covering the Adeptus Mechanicus within the Calixis Sector. Here players and GMs can find new origins for their Mechanicum characters, a new NPC to guide them within the Lathes system, additional armoury weapons and gear, and revelations for one of the more mysterious of the Lathe Worlds. Fire the Forges with these new blessings of the Omnissiah!