Tiny Tina's Assault on Dragon Keep is DLC for Borderlands 2.

Sorcerers, Wizards and Crumpets, oh my! Join vault hunters, old and new, in Tiny Tina epic quest of revenge and redemption. Tiny Tina’s Assault on Dragon Keep, the biggest and most inspired add-on content in Borderlands history, features a game within a game, as Tiny Tina takes on the role of Bunker Master in a game of “Bunkers & Badasses”. Travel through a dark and ever changing world of castles, dungeons and magic forests as you fight off skeletons, orcs, dragons and more. Explore side missions and answer riddles as you roll your insight stat to gain new and amazing loot. Join with friends to save the queen and restore peace and order to the world once more.