A great explorator fleet sets out into uncharted space, the Halo Worlds at the galaxy's edge. The armada contains contingents from every aspect of the humanity's Imperium, from the humble guardsmen, to the mighty Space Marines, all lead by the ancient tech-scholars of the Martian priesthood. They seek an ancient and priceless technology from the birth of history, but what they find is more powerful and deadly than any of them could have imagined. CONTENTS Priests of Mars Lords of Mars Gods of Mars Zero Day Exploit