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!

Go to: http://store.steampowered.com/ and download STEAM client Click "Install Steam" (from the upper right corner) Install and start application, login with your Account name and Password (create one if you don't have). Please follow these instructions to activate a new retail purchase on Steam: Launch Steam and log into your Steam account. Click the Games Menu. Choose Activate a Product on Steam... Follow the onscreen instructions to complete the process. After successful code verification go to the "MY GAMES" tab and start downloading.