How much time does it save if you get it first try?

Yeah this has been known for some time; the cannonless TAS (I highly recommend watching) uses it in a few places.

I've done the midair jump on accident probably 4 or 5 times. I actually did one in my current PB at the end of 8-5!

Awesome that you found a setup though! Thanks for looking into this. TASes can do a lot of cool stuff with the shell, as seen in the cannonless TAS.

Interesting alternative. I wonder if this can be made consistent? I'll certainly try.

Reminds me of the wall clip in BC where you do a yump off the switch in the thwomp room. I've gotten it in practise multiple times but never in a run. It also seems more consistent as big Mario. I've only gotten it once when small. Seen at 20:13 in the TAS:

After a few hours of practise, I've only gotten the extra jump about four times, and never made it all the way up to the ledge. Definitely a tough one! Do you hold y/x when doing the wall kick? Or does that even make a difference?

Also, I'm wondering why you need to release and re-press A before exiting the shell by letting go of X. Is that required to make the glitch work?

I'm sorry, it's still unclear to me whether you need to let go of and then re-press A/B after already having jumped into the air, because to my understanding that makes you lose height on your jump. Maybe I'm just reading something wrong, but that's the impression I got from your first post, where it said:

2. (Jump into the air)
3. You need to release A at just the right time, then immediately hold A again and continue holding X.

Sorry for the inconvenience!

EDIT: It in fact appears your point 3 may be directly referring to point 2. I assumed the instructions were in chronological order. Apologies, and thanks for the help!

I don't think the comparison to the walljump in 8-4 is very accurate, because the walljump has two very clear visual cues.

Could you get a video of you doing it with the input display turned on? I'm not sure I completely understand the inputs.

Wow, this is amazing, I didn't know the shell jump was possible RTA! Good work! Is there anywhere else where this would save time?

this is way harder than a walljump in smb1 tbh. On a good day, I can get fast accel walljumps 3/4 times, sometimes even better, But I cant get anywhere near as consistient at this trick. However, I have investigated my input faults on emu by making a movie of just me failing fast 8-2, and it turns out Im actually releasing B early relative to when I release X and press A. ILoveSMB, by any chance do you know the number of frames it is from the point you release A in the initial jump, to when you repress A and release X to activate the doublejump? I wanna make This semi consistient, cause at this point, Id compare the difficulty of fast 8-2 with mavpole

also I want a 22 SOB because that would be nice

I was going to TAS to figure out how many frames, but I figured that you might already know, so I just asked. cause with an actualy frame by frame setup™, this trick could be as consistient as a flagpole glitch for a top SMB runner

Update: several people including myself were able to get fast 8-2. For the wall kick strat, I found out that you don’t ever need to hold left. Here’s the setup:

1. wall kick (hold dash, push up against the wall, double tap jump)
2. full jump (Hold dash, down, and right as you do so)
3. release dash, jump and down at the peak of your jump, and immediately press jump once again

Another update: it turns out that releasing X/Y actually doesn’t have anything to do with getting the jump itself; you can hold it down for the duration of the trick(for the sake of getting the initial x-velocity, obviously). With that said, here’s what I believe to be the easiest setup for non-emulator runners. I will use the (AB to jump)/(XY to dash) button configuration since that’s what I use. I’ll also specify which button for jump/dash I use since that’s what I’m most comfortable with, but of course you can adjust accordingly.

1.) Pushing up against the pipe, hold Y and quickly double tap B to wall kick (Y button will be held down for the duration of this trick, as mentioned earlier) 2.) Crouch as you land and do a full jump with B. The timing of the crouch is important, and probably one of the hardest part of the trick; tap ↓ too late and you can’t crouch-jump, but tap too early and you’ll ground pound instead 3.) Immediately switch your D-pad input from ↓ to ➝ while in midair. This will make sure that once Mario loses his x-velocity at the peak of his jump, he will pop out of the shell without releasing ↓ (removes the need for one frame perfect input, obviously) 4.) Release B slightly before Mario reaches the peak of his jump, and tap (and hold) B at the very peak. If done correctly, this will initiate the shell jump glitch