Okay, so, here is a fast way to get stickers and music. Go to stage editor, the smallest stage will suffice. Pick out the conveyor belt, and make it as big as you can, so it's 4 squares long. Make them move stuff to the right, and then put one, and one directly under it. Then put some solid normal blocks in a small pit underneath these conveyorbelts. Like, a pit around this size:
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Above this pit, have to blocks that fall if you stand on them. Go to brawl in this stage, use bowser, and make sure you have items on very high, and only the sandbag. The sandbags will fall into the pit, where you will stand, and hit them and collect lots of shit.