You might remember some months ago I told you about a semi-secret passage through the grassy areas of Super Mario Bros. 3.
One of these stages is 3-4, which features water in some of the pits that you have to navigate.
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The same rules apply here, too, hug the wall to try and get away from a marauding Cheep Cheep and hit that dark patch at the bottom of the screen
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And you dead.
So, try to not do that, okay?