Borderlands 2's Badass Rank system has bugged out for a number of players who claim that the bug has wiped their progress. Developer Gearbox Software is currently working on a fix, but you can get more details and video footage of the bug in action below.
The bug affects PC, PS3 & Xbox 360 versions of the game, wiping all of your Badass Rank progress, but does not reset any completed challenges, meaning you are effectively locked out from earning them again. Here's a clip of it in action, courtesy of RyogaWanderer:
GameInformer reports that Gearbox has issued a statement on the matter that reads, "Our engineers are looking into this, and the information you've provided has proven to be a great resource while we investigate. At the moment, it seems to be a fairly rare issue and we'll keep you updated on when we resolve it."
Have you been affected by this? If so, let us know.