With all new narrative content, this add-on begins as Vault Hunters Axton and Gaige catch up on the story thus far via The Holodome Onslaught, a new challenge arena that lets players fight through wave after wave of exciting enemies and bosses.  While the veteran Vault Hunters join the rest of the crew at Crimson Raiders HQ and learn of recent events, players will face off against some of the game’s most memorable badasses to earn awesome, new weapons and gear along with radical new heads and skins!
 
As bonus content, this download  also includes the Ultimate Vault Hunter Upgrade Pack, which raises the level cap and gives your characters 10 new levels plus 10 new skill points to earn!

To activate the game, you need a Steam Account

• Login or register at the official
  Steam Website and download Steam client
• Install and start application, login with your Account name and Password
• Click the Games Menu.
• Choose Activate a Product on Steam...
• Follow the onscreen instructions to complete the process
• After the successful code verification, go to the "MY GAMES" tab and start downloading.