Gearbox has confirmed that the fourth and final campaign add-on in Borderlands 2’s Season Pass is Tiny Tina’s Assault on Dragon Keep. The pack will be released on PC, PlayStation 3 and Xbox 360 on June 25th for free to Season Pass holders, or for $9.99 (800 Microsoft Points) to anyone else.
The add-on revolves around a game of Bunkers & Badasses -- Pandora’s version of Dungeons & Dragons -- led by Tiny Tina. Original Vault Hunters Brick, Mordecai and Lilith are gathered around a table playing through Bunkers & Badasses and you are a character in their game. You'll experience their game as part of Borderlands 2 with Tina serving as dungeon master, narrating the action as it happens and even changing boss attributes, location details, character names and much more on the fly.
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The add-on revolves around a game of Bunkers & Badasses -- Pandora’s version of Dungeons & Dragons -- led by Tiny Tina. Original Vault Hunters Brick, Mordecai and Lilith are gathered around a table playing through Bunkers & Badasses and you are a character in their game. You'll experience their game as part of Borderlands 2 with Tina serving as dungeon master, narrating the action as it happens and even changing boss attributes, location details, character names and much more on the fly.
source