Look: The pipes that lead into the sewers are not "Warp Pipes". They're just pipes. The whole warping thing is when you jump into the pipe and are instantly transported to someplace else. In SMB3, World 1, Level 2, in the floating pipe with the Pirana plant in it, when you go inside, you're in this large chamber. Now, you don't see any large chamber on the outside. You know why? The pipe warps you to the chamber.
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In my dream, the world had suffered a terrible disaster. A black haze shut out the sun, and the darkness was alive with the moans and screams of wounded people.
Suddenly, a small light glowed. A candle flickered into life, symbol of hope for millions. A single tiny candle, shining in the ugly dark. I laughed, and blew it out.