The Fire Bar is very ancient in the Super Mario Bros franchise, this obstacle is most likely found in lava levels it has been around to annoy you from Super Mario Bros for the NES. A Fire Bar looks like several balls of fire floating next to each other. Fire Bars move in a circle so make sure your timing is on one wrong move or it might be the end of that run for you or you might turn into small Mario and if you have Ice Flower or a Fire Flower you will be super Mario.
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