The sweeping strike enchantment is a unique enchantment that can be used to increase the amount of damage your sweeping strike attack does with your sword.
The amount of damage your sword does with this attack will also increase depending on what level of the sweeping strike enchantment you use. Also, if you have an enchantment such as sharpness, the damage output for the sweeping strike will increase depending on the level of enchantment.
That said, if you are interested in this enchantment for whatever reason, the best way to get it would be to make books and then an enchantment table. You will also need to make 15 bookcases and place them around the table with a one-block buffer zone between the 15 bookcases and the table.
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When you are done, you will then need to use books and lapis lazuli to make enchanted books by placing both inside the table until you get the sweeping strike enchantment - this might take a while, but it's a surefire way to get other enchantments you don't have.
You can also use fishing poles, trade emeralds with villagers, and loot enchanted books out of dungeon chests to get sweeping strike books as well. However, if you want a constant and worthwhile way to get the enchantment book, we recommend the book and enchanting table route.
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