Green Horseshoe Balloon

Fall damage stops mattering, your jump gets much taller, and you get a second jump in the air. That combination covers most of what movement accessories are for at this stage, and it does it without asking you to give up a slot for each piece.

Wearing a second balloon of any kind does not raise the jump again, and stacking extra horseshoes does nothing either. The plain jar and balloon versions of the same effect go dead once you own this, because the extra jump they hand out is already the one you are using. Keep that slot for something that adds a number.

It needs the plain Lucky Horseshoe. If you already fused yours into an Obsidian Horseshoe, that one will not work and you need another sky chest. Check what you are carrying before you start combining things at the Tinkerer.

Letting go of jump mid-rise cuts the second jump short, which matters when you are threading a ceiling. The burst also shoves you horizontally, so you can use it to reverse direction without shedding all your speed.