You can upgrade a diamond sword with this recipe in a smithing table. This causes your sword to cause an entity damaging explosion in front of you every four hits, this is called a Soulburst. You can upgrade this to netherite, but make sure to upgrade the sword with the sculk first, as you cannot do this after the netherite upgrade.

You can upgrade a pair of iron boots using this recipe in a smithing table.  Once upgraded,  you can crouch to start floating upwards, although this does not cancel any pending fall damage.

You can upgrade any armor piece made with the listed materials using chainmail and an iron ingot in a smithing table. This gives the upgraded armor piece a  few extra armor points.

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