The Arkham Knight character that will be in Batman: Arkham Knight will be first introduced in a prequel comic.
This comic will focus on the Arkham Knight character and will take place before the events of the game. The story happens straight after the events of Batman: Arkham City with Batman still recovering after that events of that game.
Arkham Knight is a unique character that isn’t based on the Batman comic books or even movies. The comic will give you can idea of who he is and what his motives are. It’s much like the Halo: Nightfall series that introduces audiences to the Agent Locke character before they play Halo 5: Guardians.
The Arkham Knight comic book will be written by Peter J. Tomasi with artwork by Viktor Bogdanovic and Art Thibert. The first issue of the comic book will be released on March 11th, 2015. This is around three months before the game comes out on June 2nd, 2015.
It will be interesting to see who this Arkham Knight person might be. We won’t know this until obviously the game comes out. There will be a lot of more familiar Batman villains in the full game though.