highandmightyjoe
Smash Ace
First here is the video
http://www.youtube.com/watch?v=a-FXO43sUAc
This is done by ledgehopping your upB on any stage with a slanted edge, with Yoshi's being the easiest to do it on.
My theory on why this happens is this, when you use your aerial upB it has 3 frames of invincibility, if it touches ground and becomes a grounded version during this time then the glitch occurs making it stay invincible for the entire duration of the move. This would mean that you have a 3 frame window to perform the technique which feels about right from my testing with it. This may not be true, its just my theory, but it seems about right.
Hope this is helpful, and if anyone gains any new insight please feel free to help out.
EDIT: According to TheNix(thanks), this actually does work on every attack, which actually makes a lot more sense and clears up some questions that I had about how this worked. The theory seems to hold that this is done in the three frame invincible window from frame 4-6.
EDIT2: For people who are asking how hard this is to do, I just did 5 in a row on Yoshi's, here is what I did to get the timing down. Drop from the ledge then jump. Watch DK's feet, when they are parallel to the stage that is when you start your upB. By doing this I have been able to do this every time. Works the same way on Pictochat.
EDIT3: I have confirmed how the invincibility works. When recovery from the ledge with this you are given invincibility to certain attacks, mostly projectiles. You will also beat out or clank with most melee attacks. However, there is a portion of the move at the end where you have stopped spinning, but will continue to slide forward some while still flashing with invincibility. During this time you are invinicible to all attacks.
http://www.youtube.com/watch?v=a-FXO43sUAc
This is done by ledgehopping your upB on any stage with a slanted edge, with Yoshi's being the easiest to do it on.
My theory on why this happens is this, when you use your aerial upB it has 3 frames of invincibility, if it touches ground and becomes a grounded version during this time then the glitch occurs making it stay invincible for the entire duration of the move. This would mean that you have a 3 frame window to perform the technique which feels about right from my testing with it. This may not be true, its just my theory, but it seems about right.
Hope this is helpful, and if anyone gains any new insight please feel free to help out.
EDIT: According to TheNix(thanks), this actually does work on every attack, which actually makes a lot more sense and clears up some questions that I had about how this worked. The theory seems to hold that this is done in the three frame invincible window from frame 4-6.
EDIT2: For people who are asking how hard this is to do, I just did 5 in a row on Yoshi's, here is what I did to get the timing down. Drop from the ledge then jump. Watch DK's feet, when they are parallel to the stage that is when you start your upB. By doing this I have been able to do this every time. Works the same way on Pictochat.
EDIT3: I have confirmed how the invincibility works. When recovery from the ledge with this you are given invincibility to certain attacks, mostly projectiles. You will also beat out or clank with most melee attacks. However, there is a portion of the move at the end where you have stopped spinning, but will continue to slide forward some while still flashing with invincibility. During this time you are invinicible to all attacks.