Bungie's Destiny video game details leak online

IGN says that Destiny involves an alien ship that helps protect a city from monsters

Details of Bungie's first game since quitting the best-selling Halo franchise have been leaked online.

The gaming website IGN has obtained marketing materials revealing it is called Destiny, and aims to create a universe "as deep" as the Star Wars franchise,

The project had been one of publisher Activision's most closely guarded secrets.

It has a 10-year exclusive arrangement with the development studio.

Activision has previously told investors that the game would be "genre-defining" and prove to be one of its two "largest growth opportunities" over coming years, alongside the Call of Duty series.

Following IGN's exclusive, Bungie reproduced one of the images on its own site and confirmed the leak's authenticity.

Sci-fi fight

According to IGN the game will be set 700 years in the future, and feature battles with aliens to protect the "last city on Earth" after the collapse of mankind's efforts to colonise the Solar System.

A screenshot suggests the first title in the expected series will run on the PlayStation 3 and Xbox 360. Bungie's most recent releases had only run on Xbox systems.

A decision to build another sci-fi franchise will see Destiny compete with the developer's original series.

Microsoft has said it has plans for at least another two Halo games. Its most recent sequel, Halo 4, was created by its own subsidiary 343 Industries. The series as a whole has generated more than $3.4bn (£2.1bn) in revenues to date.

"You can never have sure bets and the risks involved with creating new IP [intellectual property] are always relatively high, but to have a studio like Bungie involved reduces the risk considerably for Activision due to its incredible track record," Pier Harding-Rolls, head of games research at IHS Screen Digest, told the BBC.

But he added that the publisher was unlikely to be happy about the way news of its game had become available.

"I don't think any company that wants to manage and control the promotion of their material would want to see it leaked through the back door," he said. "But a lot of leaks do go on in the industry.

"I'm sure we'll see a lot more of it at E3 [games conference] in June where games like this can be shown in a satisfying way."