Wow, two Super Mario-related posts in a row. Must be the imminent Nintendo DS Lite launch fever creeping up on me. The good people at TASVideos have collected a whole bunch of tips and tricks for various Super Mario Bros games, but these aren't your run of the mill, you-can-find-this-in-the-official-guide type tricks. Oh no my friends, do you really think I'd turn your attention to something so simple and mundane? You know me better than that. These tricks rely on glitches (not really glitches, but I can't think of a more appropriate word) in the game's programming to get Mario to accomplish all sorts of amazing feats such as bouncing off walls, "stomping" enemies from underneath, jumping on thin air and walking through walls. Not only does the site give you a looped gif demonstration of all the tricks, but they also tell you how to do it and why you can do it. Here's an example:
Walljump happens because the game does a floor check (a simple "is position divided by 16 even? Is there a solid block below him?" test) even during a wall-ejection. Wall-ejection is SMB's mechanism to adjust Mario's horizontal position properly when his left side and right side have a different inside-wall status. The game ejects Mario towards the opposite of his steering.Got that? Good. Now you try.