The majority of Batman: Arkham City's gameplay takes place on the streets, developer Rocksteady's told PSM3 magazine.
Speaking in the mag's latest issue, which features a four-page Arkham City preview with new details and screens, the developer said building a larger world in the sequel has been a "huge technical challenge".
"Interiors are locked to specific missions, but 80% of the game takes place on the streets," Rocksteady's marketing game manager Dax Ginn told PSM3.
"This means you can begin the game and just start exploring," he added, assuring the mag that a focus on freedom doesn't mean sacrificing the narrative. "Plot is really important to us," he said.
"Our objective was not to make a bigger game world just for the sake of it. We want to fill it with content, and there's no better world than Batman's universe to take inspiration from.
"We have 97 people on the team, compared to 65 on the first game. Because we've decided to make such a large world we had to bring in more artists, animators and so on. It's been a pretty huge technical and creative undertaking for the team."
Earlier this month we posted 76 Arkham City screenshots from the latest gameplay trailer.
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