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.