Batman: Arkham City's developer, Rocskteady Studios, has taken the time to outline exactly what content will be in the game, and how long it should take people to accomplish everything.
Of the main campaign, they said that it takes around 25 hours, although some "ninja QA testers" have managed to do it in around 8 hours. There will also be numerous side-quests, which can be done whenever the player wishes. These are expected to take a further 15 hours.
"It's completely down to the player when and how they want to tackle this - there's no right or wrong time. There's no other medium that can offer this kind of flexible experience where the viewer gets to tailor the experience they want themselves," said Sefton Hill, the game's director.
The game is due out this October on PlayStation 3, Xbox 360 and PC platforms.
Source: The Guardian