Batman: Arkham Origins

Batman: Arkham Origins is a prequel to Batman: Arkham Asylum and Batman: Arkham City taking place in the first year of Batman's career. It has a portable follow-up done by Armature Studios called Batman: Arkham Origins Blackgate.

Gameplay
It plays very similar to the other games in the Batman: Arkham series.

Plot
Batman is being hunted on Christmas Eve by 12 assassins hired by Black Mask.