When the Horus Heresy broke out, the galaxy fell into turmoil. In the Belt of Iron, an area characterised by a preponderance of forge worlds, long-held grievances turned into outright war between Mechanicum factions, and the Titan Legions aligned with the various forge world marched in defence of their allies… Discover the dramatic events of the Cataclysm of Iron, when forge world fought forge world, in this 96-page hardback supplement for Adeptus Titanicus. Harness the strengths of seven different Titan Legions using two new maniples, and bring the might of four Knight Households to bear against your enemies. Play out the story across four narrative missions – or create your own with new Echoes of Glory rules that provide you with powerful tools to play your games in whatever manner you choose. Inside this book you will find: • An overview of the Cataclysm of Iron campaign • Background and Legion-specific rules for seven Titan Legions: Atarus, Astraman, Ignatum, Venator, Laniaskara, Kulesaetai, Damicium, and Tritonis • Two new maniples to use in your games • Background and rules for four Knight Houses: Col'Khak, Moritain, Gotrith, and Vextrix • Full colour examples of paint schemes and heraldry for Titans and Knights • Four narrative missions based on the dramatic events of the story • Echoes of Glory rules for creating your own missions across five mission types and three world types