Super Mario 63 Redux is a remake of Super Mario 63, a Mario Flash fangame that takes mechanics from Super Mario 64 and Super Mario Sunshine and puts them in a 2D Mario game. Currently in development as of this writing, the game plans to have completely new graphics, original music, and wholly rewritten dialogue.
Vexxter, Tomothy, and roblox8192 all work together for this run to beat the "Tiny Demo" — which only includes four levels — as fast as possible by abusing a number of glitches and peculiar mechanics. For details on the the effort put in the run and mechanics abused, you can read the authors' notes.