[MKWii TAS] New Ultra Shortcut on Mushroom Peaks

After almost 16 years, one of the most iconic custom tracks in Mario Kart Wii history finally has what it's been missing. An ultra shortcut.

Huge thanks to ‪@EPIK95‬ and ‪@mikul958‬ – without them this would not exist.

Track info: https://shorturl.at/zaqGf (v1.0) by ‪@MrBean35000vr‬ and Chadderz

-104.258 from No Glitch TAS BKT (3:29.366 by ‪@SwareJonge‬ on RC5)    • [MKW TAS] Mushroom Peaks - 03:29.366  

Music: Super Mario World Restored - Athletic Theme    • Super Mario World Restored - Athletic  

Back in early November, I was in a VC with Epik and Mikul. Epik was working on Mushroom Peaks for the CTGP Christmas Update and was looking at all the respawns.

Epik noticed that the respawn for CP1 put you directly on the first mushroom. For whatever reason, respawning on a mushroom causes all sources of external velocity (including gravity) to disable, so you end up floating in the air. You also have a fixed -0.25 Y velocity, which is a result of retaining the slow falling speed from after respawning (for context, this is 480x slower than terminal velocity).

Initially, this seemed like another useless CT quirk, but Mikul noticed when you wallride on the surrounding walls of the track, you can end up slowly GAINING height at speeds of less than 1 unit per frame. The walls being 30000 units tall; reaching the top took about 12 minutes. From there, he was able to freely float out of bounds, perform an ultra to reach the end of lap 1, then do it again to get a 30 second lap.

This was a pretty incredible find, and we all discussed potentially saving it for April Fools provided someone made a flap TAS. The problem with this is that in order to optimally complete the lap, we believed you would need to fall back down to the height of the track before entering the lap, which was at a Y position of ~18800 and would take another 12 minutes. Optimising this 25-minute-long flap setup would either take an eternity or require utilising certain scripts that none of us were prepared to set up. That didn't stop me from still making a preliminary 24.844 flap.

Obviously, this was still a big flaw in the track, so we devised a plan to try to keep the respawn, while preventing it from harming gameplay in CTGP (by making it impossible to encounter). Epik remade CP1 such that it was only 30 units thick and placed it at the first ramp. In normal gameplay, not only would you boost past it immediately, but in most cases you would pass completely through it without ever entering it.

Fast-forward to December 25th, and v1.0 of the track got into CTGP! Mushroom Peaks (as it stood in CTGP) officially had an ultra shortcut! Unfortunately, in January, the person who placed the respawn on the mushroom in the first place noticed their mistake, and fixed it, patching out the ultra in v1.0.1. This made members of The Track Breakers lose interest in showcasing it, however I reached out to Mikul (who had planned on TASing it) and he said it was okay for me to upload on my channel. Two days ago, amidst exams and other TAS projects, I finally forced myself to take a stab at the ultra so that I could get a video of it out in time for April Fools Day.

To limit the amount of time I'd need to spend watching the TAS back, I looked for the fastest way to ascend the walls; finding a 3.9 speed wall after the first turn, followed by a 1.8 speed wall to reach the top of the first hill, and then making my way over to the 0.6 speed surrounding wall near the first turn. I was limited in wall choice as most result in you ascending into OOB planes. After this, I waited for about 12 minutes to fall back down to the track height, and performed a delayed lap count to prevent having to turn around slowly entering the lap (I was using Spear for its speed so had bad handling). Finally, I entered the track, landed back on the second to last ramp, hit the last KCP on the turn, then drove forward to complete the lap.

On replaying the run, I noticed that hugging against walls gives you a brief initial position update that moves you up by ~65 units. This helped me gain height a little faster in the early stages of the setup. I tried seeing if I could use it as I climbed the first hill, and found that the initial position update happens repeatedly if you are facing the wall at a precise near-parallel angle. Excited, I tested it on the wall beside the finish line, and reached the top in only 15 seconds by essentially wallclipping every other frame! I decided to call this technique "wallclip stacking". After reentering lap 1, I performed the ultra 3 times and got a time of 2:31.

I immediately switched to the combo with the highest handling stat, since speed was no longer a concern, and optimised the 3lap time down to 1:52, 1:49, 1:47, and finally 1:45. This massive timesave can be attributed to the better handling, barely clearing every single wall, and taking a direct line to the finish line on lap 3.