As anyone playing this game knows, you can't double jump...

... or at least that's what the developers thought!

After seeing video proof of it happening, which you can check here (jump to 1:55): I decided to investigate. And after fiddling with the TAS for a while, I finnaly figured this out.

The basic idea is simple: jump, trigger the auto-block while mid air (which relies on your speed stat and RNG) and then you can jump again.

With that trick in your arsenal, you can enter Machine Pit via the Barbarian Cave / Undead Yard sidequest (available as early as NumeNume River) and use the double jump to access the levers needed to unlock the dungeons, as well being able to reach the compiler ship area. This allows you to skip Venon Jungle and Dry Land entirely! It's a 1:30h time save, maybe even as far as being 2h!

Sounds cool, right?

However, actually pulling it of ain't easy! I've given you the basic idea for noobs, but there's more to it than that. Turns out you have to:

1- Jump exactly 1 frame before getting hit. If you jump earlier, it won't work. If you jump late, you get hit. So right off the bat, we're already trying to perform a frame perfect trick 2- Have the RNG be in your favor to trigger the auto-block. The higher your Speed stat, the better. In the context of a speedrun, it'll happen rather frequently, I'd say once every 3~5 hits. 3- And we're not done yet! After getting both of the above, you have to jump again on the 18th frame after the auto-block goes off. Another way of saying is jumping 8 frames after the red guard dissapears (10 frames after the auto-block). Jumping early isn't a problem, as your controls are locked. However, jump too late and the trick won't work.

Here's the trick in action:

That's the explanation behind the history and mechanics of the trick... but if you want to actually pull it off, there's a couple of things to do to help you out: 0- Jump on 1 enemy at a time. Multiple enemies on screen just mess with you, it's better to kill everyone on sight and leave a single foe alive. 1- Calibrate your timing for the initial jump. You're supposed to spend only a single frame in the air before getting hit, so take a close look to when you get hit to calibrate your attempts: if most of the time you are getting hit while already in the air, it's because you're jumping too early; if most of the time you are getting hit while still on the ground, it's because you are jumping too late. So constantly delay / antecipate your jumps to try and strike a balance between both. Personally, I tend to favor the ground (late) side, it's easier to jump too early than it is to jump late. But that's just my taste. 2- As soon as you jump, move the analog in the direction you want to go. It's amazing how often you 2x Jump just to miss the platforms because of a lack of range, if you don't change directions quick enough. So to avoid that, move the analog as soon as possible so your character does the same. And as a bonus, that movement can sometimes prevent you from getting hit altogether, in cases you jump too early, so it also speeds up attempts by a bit. 3- For that half second after your first jump, try to mash as fast as you can. Personally, I do a 3 press burst, but you can do it however you want; at any rate, the faster you can press, the higher your chance to hit the right frame. However, don't overdo it, or you'll get tired rather quickly, so try to find a "setup" you feel confortable with. 4- If you're doing it for a while and failing, STOP. Just stop, take a deep breath, release the controller, maybe even shake your hands violently to "erase the muscle memmory", reposition yourself on the chair and just try fresh. I know it sounds like a lot, but it only really takes 2~3 seconds to do all of that, so do it. And don't think of that time as being idling or wasteful, think of it as a time investment / setup to help you nail the trick: this will help relieve hand stress and make it easier to succeed, as well as having the placebo effect of "I'm doing something to improve, now it WILL work" to keep morale high, so shia la beuf it and keep going. 5- Practice. It'll suck in the beginning, we all had our 30min DoubleJump split. But as you do more and more attempts, you'll eventually get the hang of it, and for as awful as a double frame perfect trick with an unfavourable RNG roll might sound, it's really not as bad to perform.

And those are the things I do to help me perform the Double Jump.