Aquatic Affinity is a unique enchantment in Minecraft that makes it so that players do not suffer any mining penalties when trying to mine blocks while floating or underwater.
Usually, players will experience a small delay in destroying blocks when mining without an Aquatic Affinity Enchantment item. But if you grab a piece of armor enchanted with aquatic affinity, you can mine faster while floating and in water. In turn, aquatic affinity also makes it easier to get blocks that you can only get underwater.
So if you're interested in this enchantment for some reason, the best way to get it would be to make some books and then an enchantment table. You will then need to create 15 bookcases and place them around the table with a one block buffer between the 15 bookcases and the table.
Related: How to Make an Enchanting Table in Minecraft
When you're done, you'll need to use both Books and Lapis Lazuli to craft Enchanted Books until you get the Aquatic Affinity Enchantment.
You can also use Fishing Rods to get an Aquatic Affinity Book, but you'll need to get both Lure and Sea Enchantment Luck on the Fishing Rod.
Trading emeralds with villagers and looting enchanted books from dungeon chests for aquatic affinity books is also an option. But overall, we recommend either Fishing Rod or Enchanting Table Routes as the best options to get the book.
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