Double-click flag so that the music syncs! You can replace characters by going into their costumes and replacing the poses with your characters' poses. You can also change some of the animation code if you want it to look different. btw. the bg roughly is at 15 fps, notes and scratch cat (partially???) run at 30 fps, this is bc game boy games commonly had lesser fps for animated sprites, but used the smooth 60 fps of the gameboy for sprite movement and such.
SquigglyTuff for the engine Nintendo, because of the gameboy(?)