Warhammer 40,000: Inquisitor – Martyr is an open world Action-RPG developed by NeocoreGames in a close partnership with franchise owner Games Workshop. 

The game is set in the grim future, 41st Millennium of the Warhammer 40,000 Universe. The main location where the game takes place is called the Caligari Sector in the Segmentum Tempestus of the Milky Way Galaxy. The game space includes numerous subsectors, solar systems and points of interest.

Warhammer 40,000: Inquisitor – Martyr is an ARPG, featuring a 3D-rendered world presented in a top-down perspective, and focuses heavily in combat situations, investigations, missions in a traversable, open galactic sector. Here players can complete the single player campaign (story missions) or choose other activities on the Star Map, which can be done in any order, if the character overcomes their difficulty level.

Players can choose from three different classes (Crusader, Assassin and Psyker), each with three different backgrounds for different playstyles. 

Development of the game started early 2015, after a pre-production period. The game was announced in July 2015 with a CGI trailer.

In February 2017, a campaign titled The Founding was launched. It allowed early adopters to purchase the game and see its development through, providing essential feedback. A development Roadmap was published detailing current and future updates. 

In August 2017, the game entered Steam Early Access to allow more players to join the game's final development phase and provide more feedback on the game. 

This is the official Roadmap for the Steam Early Access phase:

The full game is set to be released in Q1 2018.