PC/PS3/Xbox 360 RPG shooter Borderlands will be getting a second piece of downloadable content in the next few weeks. Mad Moxxi’s Underdome Riot is set to arrive on December 29th for the Xbox 360 and on January 7th for the PS3.

Underdome Riot ($10 or 800 MS Points) adds three new "Riot Mode" arenas. You (and up to three friends via co-op) will fight off waves of enemies in exchange for some sweet new loot and a couple extra skill points. The DLC also adds a much-needed feature to the game: a bank for storing your extra equipment.

No release date was provided for the PC version of Riot but rest assured the content will appear on that platform as well. Yesterday the first DLC, Zombie Island, was released for the PC, which was a couple weeks after it hit consoles.