This 98-page softback book contains:
- Background, art, and fiction giving you an overview of the Idoneth Deepkin's history and unusual ways of war
- A description of their many units, along with detailed photography and artwork
- Faction rules including battle traits, battle formations, heroic traits, artefacts of power, Spells, and Manifestations
- 21 warscrolls, covering units, terrain, and Manifestations
- A Spearhead guide, including gameplay and hobby advice, along with a set of warscrolls and army abilities for the Akhelian Tide Guard
- Narrative Path to Glory rules, including the Anvil of Apotheosis, allowing you to create your own hero
- Rules for two thematic Armies of Renown and two Regiments of Renown that can be added to other Order armies
- A handy reference section with army abilities, magic, and battle traits

This book also contains a one-use code to unlock Order Battletome: Idoneth Deepkin content in Warhammer Age of Sigmar: The App.