Since I have the record for speedrunnuing this game, I thought that I'd like to share a few tips on how to speedrun this game here:

Earth:

• Spam jump to head up the first hill to avoid losing time running into walls
• Do not jump onto the zombie. You will die
• When you collect material from the tree, spam action as you get to the top hill to build a ladder, as well as holding up and to the right (it will move you to the left due to the different physics on the ladder).

Ice:

• When spawning from Earth, do not hold right. This will cause the flint to despawn, soft-locking you (unless you are doing a glitch run).
• Jumping onto the first set of stairs at the fastest possible time requires hard timing. Even my (glitchless) WR run messed it up. The time that you must jump should be a bit after collecting the flint.
• The TNT does not actually hurt you, so don't be afraid to stand near it after spawning it. You can spawn the TNT from very far, so spam action once you have the materials for the TNT until it spawns.

Lava:

• When spawning in from Ice, try not to hold left, as you will fall into the lava no matter how long you are holding.
• (This is actually only available in lava training mode if you wait for a bit after starting, my mistake) The first blaze has a chance to spawn behind the bottle, giving the fastest possible time. My WR run did not achieve this luck level.
• To jump over the lava in the fastest possible time, jump when you've reached the 2nd closest block from the lava pool.

Air:

• Just hold right. There is no faster possible run than holding right on this level.
• The first inputs to do at the start should be hold right, and immediately jump when spawning.
• Your bow does not run out of arrows. So spam arrows until both phantoms get hit.

Those were some important tips that I thought I'd share! I made this so that there could be some competition for spots on the leaderboard. Hope you found this useful!