If you've been itching to play the new game from Bungie, the creators of Halo, you won't have to wait too much longer.

The company's new title, codenamed "Destiny," is scheduled to hit store shelves next fall, and should be playable on both the Xbox 360 and Microsoft's still officially unannounced next-generation system.

Details of the game came out when a contract between Bungie and game publisher Activision was made public as part of the ongoing lawsuit between Activision and Call of Duty founders Jason West and Vince Zampella.

Even in an industry where leaks are commonplace, this is a huge one.

Bungie has agreed to develop four "massively-multiplayer style sci-fantasy, action shooter games" in the Destiny franchise for Activision, with one coming out every other year starting next fall. In the intervening years, Bungie will release downloadable expansion packs (codenamed "Comet").

Exactly what the contract means by "massively-multiplayer style" is something of a mystery. It's unlikely that even Bungie could produce a new online game every two years. One possibility is players will be required to authenticate their game online whenever they want to play, as is the case with the recently released Diablo III. There have been rumors that the next-gen Xbox will require all games to do this, which is also how the system will reportedly restrict used games.

The contract released in the court filing was signed two years ago, and it's entirely possible elements of it have been adjusted since then. Under the initial terms, though, Bungie's first game in the series will be exclusive to the Xbox and its successor for a year. PlayStation 3 owners will be able to try it out in 2014, though it appears PS4 owners may not be able to.

The contract also details the financial agreements between the companies, which is how it managed to be introduced into evidence in the West/Zampella trial. Bungie will earn a very generous royalty for the games, pocketing between 20 and 35 percent of the game's operating income, which is the amount left over after Activision is reimbursed for development, marketing and other expenses.

Bungie also retains ownership rights to the game's intellectual property and keeps Bungie.net (and all income it might collect) under its control.

Interestingly, "Destiny" isn't the only thing Bungie's working on these days. The contract confirms the developer could be working on a follow-up to Marathon, the 1994 Mac game that first put it on the map.