A team comprised of well known speedrunners including Tyler Kehne, MKDasher, sonicpacker, Snark, SilentSlayers, Gaehne D, Eru, and To managed to pull off what's being called the 'Holy Grail' of Mario 64 sequence breaks.
It's being called the 'Moat Door Skip' and it was previously presumed impossible....until now. Here's a mere segment from the lengthy post, which describes what this team had to go through to achieve their goal:
“Many years ago, the SM64 community demonstrated with hacks that the moat door was fully functional underwater, and that there was a 1 frame window where Mario could run underwater and open it. Still, the uncooperative geometry of the Castle Grounds map seemed to indicate that the Moat Door Skip would always be a plumber’s pipe dream. However, in 2015 Tyler Kehne identified the parallel universe (PU) glitch, and he immediately realized that it could potentially be used to solve the problem. After overcoming several seemingly fatal issues with applying the glitch, he theorized a method for Moat Door Skip that takes a detour through Vanish Cap Under the Moat. Tyler and sonicpacker then collaborated to demonstrate this method, which required the collection of 10 stars.”
“But in order to make Moat Door Skip useful for a speedrun, the team had to find a way to quickly get into VCUtM with only 0 stars. The only known way to do this involves jumping with a very high negative speed, which results in a proportionally large vertical displacement that can traverse the depth of the water in 1 frame. In order to make the trick work, the team had to design a far more potent BLJ than anything ever seen before on Castle Grounds. SilentSlayers and sonicpacker set to work on surveying for potential BLJs, and eventually they found one on the far side of the lake that allowed several thousand speed to be accumulated. Tyler then figured out how to route the speed to an appropriate jump location, and the vision of the Moat Door Skip was fully realized!”