Obtaining
Right door in Desert Fortress, one way to get to the chest is the tribal spear of summoning, and building stairs. You can also build stairs with clones, which is not recommended.
Another method is via the obsidian wall spell. Turn off all auto-spellcasting, and build a wall about mid way to the chest. Use fireball to break down the wall until you can jump to it with the pogo-stick + feather. Immediately build another obsidian wall and repeat.
One last method is using The Octopus King crown with obsidian with the sponge. You may have to cast an obsidian wall to stop octopuses spawning near the chest and blocking your path if you're unlucky. Once there's an octopus king above you, simply jump, and they will put their tentacles below you.
Description
"These awesome rocket boots allow you to jump in mid-air, so that you're basically flying!"
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