Irrational's Ken Levine has explained why the studio didn't make BioShock 2. After the success of the original game set in the underwater city of Rapture, it seemed like a dead cert that the team would follow it up, but it decided a direct sequel wasn't the right project.

Speaking to at gamescom, Levine said that there were discussions over a sequel, but that none of the ideas were interesting enough for the ambitions the studio had.

"There were discussions about it," Levine told at gamescom. "We knew the timeframe it had to come out in and we knew that the company wanted more stories in rapture and neither of those were interesting to us for the ambitions we had. And so we talked about it for a little while and it just wasn't something we thought would be challenging enough for ourselves and would be a product that people would think, as a studio, would just be repeating ourselves."

Levine and Irrational decided to make a BioShock game not set in Rapture, with BioShock Infinite taking place in sky city. Read more of what Ken Levine has to say in our full interview.