Thor
Smash Champion
Here is a video of the tech, or at least what motivated this search [it is probably a significantly simpler tech, I'm gonna guess the latter and I'll explain later]. I did this in tournament accidentally and then decided to look into it. I did this on NTSC 1.02 and tested on NTSC 1.02 as well. I am unsure if holding a bomb influences the tech, but I do not believe so. https://www.youtube.com/watch?v=NUnNNhNV8yk&t=27s
If Link catches a boomerang while ALREADY helpless after up+b [NOT mid up+b - if it were that easy I'd be writing a much nicer post], he regains actionability and is no longer helpless. Unfortunately, I could find no consistent setups to achieve this, with or without a jump. The only way I managed to make it happen a few times was with boomerang smash thrown, angled up, and using double jump somewhat quickly into an aerial up+b. Link would then fall a considerable height but regain his up+b [I tested on the lower right part of Temple, I could see Link doing up+b a second time in the blastzone before dying].
This tech works with both Link and Young Link. If you want to do this yourself, the easiest, most consistent way I found for me was to use Young Link to try it. I went to the edge of a side platform of Battlefield and would jump off and upward smash throw the boomerang, then quickly jump and shortly after up+B basically in place in the air [if you start falling between the jump and the up+B, you are up+Bing too late, but if you do immediate jump up+B you are going too early - try waiting until the boomerang has almost stopped heading out, then jump and up+B near the top of the jump... not sure I'm explaining this well]. Done correctly, Young Link would fall helplessly past the ledge, but catch the boomerang and could up+b back to ledge. I actually almost managed to land back on the side platform once or twice.
If someone wants to investigate different double jump timing, there may be a way to make this consistent with Link, or at least feasible, but I did not find one. The main issue is that going too soon causes the boomerang to just miss [it seemed], and if you go to late, you catch the boomerang mid-up+b, which means there is no catch animation and you don't get another up+b or avoid helpless after the current up+b. The closest I got to consistent was trying to move forward most of the time but not all of it, and needed a double jump, which is relatively consistent with the video. If anyone wants to search for one [I will probably search for a little longer], finding one that starts while Link is already falling is going to be most useful, because it can be done after being launched for recovery. I do not have someone who can keep launching Link offstage with something like Falco fsmash to test with, which made testing harder.
As for the tech I think ACTUALLY happened in the video? Link's boomerang catch animation can be cancelled with shield, jump, and/or special [I could not seem to cancel it with jabs, tilts, or smashes, and pressing Z seemed to cause a lightshield, not a grab] (although you can pseudo-grab cancel via bringing up shield and immediately pressing A). So I think I landed, caught the boomerang, and since I was holding R, instantly brought up shield. This is more practical for recovering, because you can smash throw boomerang at or above ledge and try to time it to catch it somewhere in the landing animation to avoid lag. I didn't spend much time searching for it, since I spent an hour testing the aerial boomerang cancel, but if someone wants to hunt for those, that's probably a useful tech as well.
P.S: I did NOT test any wall-bounce setups for this tech - there may be some way to make this very useful on over half of the legal stages that I didn't even look for. I may look for those later, but the purpose of this post is simply to discuss doing it with no objects to interfere with the boomerang.
If Link catches a boomerang while ALREADY helpless after up+b [NOT mid up+b - if it were that easy I'd be writing a much nicer post], he regains actionability and is no longer helpless. Unfortunately, I could find no consistent setups to achieve this, with or without a jump. The only way I managed to make it happen a few times was with boomerang smash thrown, angled up, and using double jump somewhat quickly into an aerial up+b. Link would then fall a considerable height but regain his up+b [I tested on the lower right part of Temple, I could see Link doing up+b a second time in the blastzone before dying].
This tech works with both Link and Young Link. If you want to do this yourself, the easiest, most consistent way I found for me was to use Young Link to try it. I went to the edge of a side platform of Battlefield and would jump off and upward smash throw the boomerang, then quickly jump and shortly after up+B basically in place in the air [if you start falling between the jump and the up+B, you are up+Bing too late, but if you do immediate jump up+B you are going too early - try waiting until the boomerang has almost stopped heading out, then jump and up+B near the top of the jump... not sure I'm explaining this well]. Done correctly, Young Link would fall helplessly past the ledge, but catch the boomerang and could up+b back to ledge. I actually almost managed to land back on the side platform once or twice.
If someone wants to investigate different double jump timing, there may be a way to make this consistent with Link, or at least feasible, but I did not find one. The main issue is that going too soon causes the boomerang to just miss [it seemed], and if you go to late, you catch the boomerang mid-up+b, which means there is no catch animation and you don't get another up+b or avoid helpless after the current up+b. The closest I got to consistent was trying to move forward most of the time but not all of it, and needed a double jump, which is relatively consistent with the video. If anyone wants to search for one [I will probably search for a little longer], finding one that starts while Link is already falling is going to be most useful, because it can be done after being launched for recovery. I do not have someone who can keep launching Link offstage with something like Falco fsmash to test with, which made testing harder.
As for the tech I think ACTUALLY happened in the video? Link's boomerang catch animation can be cancelled with shield, jump, and/or special [I could not seem to cancel it with jabs, tilts, or smashes, and pressing Z seemed to cause a lightshield, not a grab] (although you can pseudo-grab cancel via bringing up shield and immediately pressing A). So I think I landed, caught the boomerang, and since I was holding R, instantly brought up shield. This is more practical for recovering, because you can smash throw boomerang at or above ledge and try to time it to catch it somewhere in the landing animation to avoid lag. I didn't spend much time searching for it, since I spent an hour testing the aerial boomerang cancel, but if someone wants to hunt for those, that's probably a useful tech as well.
P.S: I did NOT test any wall-bounce setups for this tech - there may be some way to make this very useful on over half of the legal stages that I didn't even look for. I may look for those later, but the purpose of this post is simply to discuss doing it with no objects to interfere with the boomerang.