Alright so we (should) all know the portrait in the cascade kingdom that allows you to travel to Bowsers kingdom, well a very difficult jump actually lets you get from the tiny island in the sky to the actual level, allowing you to skip most of the game. Here's the tutorial, and here's a video of the trick being completed Sorry if this trick has already been commonly used, but as my name says i'm not a speed runner. While this jump could skip about 3/4 of the game it's also very difficult and I would advise practicing it beforehand. Hope this helps and i'm again sorry if this has already been discovered and I really do hope someone uses this trick. Thanks!