@WingedFish: #28 Yes, this is impressive. Most impressive, as Vader/Anakin would say.

@HyperBMan: #27 SMB has glitchy contact physics. Jumping over piranha plants like that is possible in-game, w/ no cheating. The glitchy contact physics help make the game (really good) speedrun material.

@3Dangerous3Dash: #23 The precedent to Nintendo Power was a newsletter called "The Nintendo Fun Club". The minus world glitch was documented in it. As for it's origins, I imagine someone who reached the L-pipe of 1-2 attempted running, &/or jumping, &/or backwards jumping to reach the top of the screen, to continue right.

There are multiple ver.s of the minus world in the Japanese ver. of the game. This was also documented in the same fun club newsletter. Btw, I don't know the full extent of it, but basically, the minus world works out like this: When the player runs across the top screen of 1-2, the game activates the "welcome to warp zone" on-screen text. When this happens, the game/program pointers for where the pipes lead to changes. By bypassing this, the player(Mario/Luigi) can access the default location for where the pipes' pointers were originally set to. In the game code/program, a blank space is actually 36. So, the "minus world" is actually world/level 36-1. This is further proven by the fact that not only does the hud show a " -1", but also the restart-after-game-over code functions as it should, if you should get a game over un the minus world.

@kyuubikid213: #7 Anyone can w/ practice. Don't doubt yourself.

@Shugo: #21 There are some glitches in the game that do this.

Again, SMB has glitchy contact physics, & also some random glitches like what Shugo pointed out.

This isn't hacked, to me. This is just a very practiced, & well-timed speed-run. This guy deserves props!