Rocksteady's Arkham Asylum sequel has "over 25 hours" of gameplay, game director Sefton Hill says.
Players will need that long to wrap up the title's story, Hill told The Guardian.
Meanwhile, side-missions will cover "15 hours" of gameplay "off the main path" and can be tackled at any point.
How will the experience change over time? Players will start off "enjoying running around the Arkham City Streets", but then "fast forward 10 hours" and they'll be swooping hundreds of metres through back alleyways, gliding into gangs of thugs and taking them out in seconds, Hill explains.
The title sees former Arkham Asylum inmates given free-reign over a guarded part of Gotham, the titular Arkham City. It turns out to be just as bad an ideas as it sounds.
The game begins with Bats trying to keep the peace, although things go pearshaped when former flame Catwoman is flagged for execution.