So, if you're like me and play tetris at every idle opportunity that presents itself and like to play WFC worldwide a lot, you might get annoyed by the mario theme constantly playing in the background. In marathon mode you have the comforting fact that music changes every level, but it still just cycles the same 10 BGMs over and over again. Another annoying thing is that the mario themes play disproportionally often in comparison with the other (more interesting) music. Now because of all these complex factors, I've decided on a simple solution: simply remove all background music in Marathon and WFC games. The puzzle, touch, push etc. games still have music. Download: http://mufunyo.net/tetris/Tetris_DS_(0366)_BGM_hack.zip Simply apply the patch to your ROM and there she goes. Works with your existing save (obviously), and isn't detected by WFC. Thanks go to FAST6191 for having lots of info around on the forum regarding SDAT files, and kiwi.ds for the very handy structs that I used to find out where to aim my hexeditor.