From the game Super Mario Bros. 3 for the NES.

Use a P-Wing in Bowser's Castle and when you reach his chamber, fly up the wall on the left. When you reach the top, keep flying left. If you drop to the other side of the wall, you'll fight Bowser in that room instead, but that's not the real glitch. Instead of dropping down, run back the way you came and fight Bowser in the first room you entered. He'll have no fireballs, even though he's still trying to breathe them out.

Taken with permission from Flying Omelette.

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.