DLC for The UnderGarden unexpectedly showed up on the Marketplace earlier today. The “Ludwig Pack” will set you back 160MS points and it will bring 2 new levels and 3 new achievements to the game. That’s all we can confirm for now as there is very little information available on the subject. Here is the official description as listed at xbox.com:

Download 2 additional levels for The UnderGarden and discover new ways to solve puzzles!