The cover for Age of Sigmar RPG was created by Johan Grenier, who has worked on many Age of Sigmar products including Realmslayer. The cover includes a heroic group fighting the undead legions of Nagash, Lord of Death, and the forces of Chaos. The party includes a Knight-Questor of the Stormcast Eternals, an Excelsior Warpriest, an Isharann Tidecaster of the Idoneth Deepkin, an Endrinrigger of the Kharadron Overlords, and a Kurnoth Hunter of the Sylvaneth, all character types playable in the game.

In the game, players take the roles of heroes of the Mortal Realms attempting to fight back the forces of Chaos, Death, and Destruction. Initially characters are created with Archetypes, which present species, attributes, core skills, talents, faction influence, and starting equipment. Archetypes available for the game include Knight-Questor and Knight-Incantor of the Stormcast Eternals, Auric Runesmiter of the Fyreslayers, Aether-Khemist of the Kharadron Overlords, Isharann Tidecaster of the Idoneth Deepkin, Witch Aelf of the Daughters of Khaine, Excelsior Warpriest of the Devoted of Sigmar, Former Freeguild Soldier of the Free Peoples, Kurnoth Hunter of the Sylvaneth, Skink Starpriest of the Seraphon, and the mysterious Realmswalker. The book also includes rules for creating characters without Archetypes, and future products will expand player options from outside the Forces of Order.

 The game uses a D6 dice pool system. Players create their dice pool by adding Attributes (physical prowess, intelligence, and strength of will) and Skills (competency and experience in a particular area.) Players also will have Talents (including spellcasting, aethercraft, or channeling the power of Sigmar in strikes.)

The Mortal Realms, the setting of the game, is presented in an overview in the book and also includes a dedicated chapter on the Great Parch in Aqshy, the Realm of Fire.

Cubicle 7 announced the license to produce the Warhammer Age of Sigmar Roleplaying Game in 2017 (see “'Warhammer Age of Sigmar Roleplaying Game'.”) The publisher released another Games Workshop licensed RPG – Warhammer Fantasy Roleplay 4E late last year (see “'Warhammer Fantasy Roleplay Fourth Edition' Launches This Summer.”)