There’s plenty of indie games out there, but once in a while, we hear all about the great successes small developers were able to achieve. Like The Behemoth, developers of Castle Crashers, who just announced that their game has topped 2 million players.

Castle Crashers was released on the PlayStation Network and Xbox Live back in August 2008, and was well received by players and the media. It’s still available on both platforms for just $10.

As part of their weekly tradition, Microsoft has announced what game will be released on Xbox Live Arcade this week: not a game, but better still – downloadable content for Castle Crashers.

The “King Pack” comes in at 160 Microsoft points ($2), adding two new playable characters, a party-healing spell, three new weapons and a seal animal orb named Pelter.

It will be available starting today for the Xbox 360-exclusive downloadable beat ‘em up title. Microsoft also announced that next week’s Xbox Live Arcade game will be The Maw, which will be available starting January 21 for 800 points ($10).

Developer Behemoth confirmed today that its downloadable beat ‘em up title Castle Crashers will sell for 1200 Microsoft points ($15) on Xbox Live Arcade when it is released on August 27.

The game was previously listed for 1800 Microsoft points by Microsoft, though both Microsoft and Behemoth later clarified that the price point had not been finalized at the time.