In Super Mario World, various glitches exist that write values to unintended parts of memory, allowing extreme degrees of manipulation of the game.
While chaining many of them together can expand this ability even further and allow full control of the game so that it can be rewritten on the fly (called Arbitrary Code Manipulation, or ACE), even a single such glitch is enough to warp Mario directly to the credits and as such skip the entire game, as seen in the footage.
In the footage, Yoshi spits out an item while in a glitched state on a spinning platform, which has the effect of immediately loading the credits. As a humorous side effect, some parts of the credits, such as Mario's walking animation, are loaded incorrectly, causing him to spin onto the scene instead of walking.
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