Gearbox has just announced their second DLC, Mad Moxxi's Underdome Riot. It's coming out this month on December 29th for the Xbox 360 and January 7th for the PS3, with a pricetag of $9.99. Mad Moxxi's Underdome Riot offers three new Riot Mode arenas (along with achievements for performing well in them), the option to store your loot in a nifty bank and the ability to earn two additional skill points, no matter your level.

In case you were concerned about the fact that this pack is based on "Arenas", a rather small portion of Borderlands, Gearbox Software says that Mad Moxxi's Underdome Riot is "not just new deathmatch areas. This is an entirely new game mode."

"Think ODST's 'Firefight' or Gears of War's 'Horde Mode.' Cash, prizes and competition!" CEO Randy Pitchford said in a statement from Gearbox. "It's like Smash TV in co-op FPS, but in the Borderlands."

Gearbox reps say the new Borderlands downloadable content "expands greatly on the possibilities of combat as well adding a ton of new rules such as vampire mode or low gravity mode..."

Joshua says: Gravity mode, eh? Vampires? And that screenshot? Seems awesome! Can't wait to see how the prizes work.