Depth strider is a unique enchantment for boots in Minecraft that allows the user to have increased underwater movement speed. Along with this, with each level of the enchantment, the player will gain a more movement speed to the point of having the same movement as on land with the third level.
Another cool thing about this enchantment is that it can be applied to horse armor and works, but you will need to be in creative mode for this to work.
That being said, if you want to get this awesome boot enchantment, you're going to need to try and do a number of activities in the game. What these things entail is as follows: enchanting books, looting dungeons, fishing, and trading.
Starting with the best option, enchanting books is probably your best long-term approach to getting the enchantment, depth strider. It's also relatively straightforward to do. In short, you are going to need books, an enchanting table, books, and lapis lazuli.
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You will then need to make and get all of that along with 15 bookcases and place them around the enchanting table with a one-block buffer zone between the 15 bookcases and the table.
Once you got everything placed, you will be able to use experience points to farm enchanted books by placing both the books and lapis inside the table until your enchantment shows up.
Takes a while, but it is overall the best way to go about it. However, if you want to try some other methods instead, start with fishing. You can fish using a fishing pole, and if you have both the lure and luck of the sea enchantments, there is a chance you can get enchantment books.
After that, there is looting dungeons, whereas you can sometimes find the books in treasure chests. Then the final method is to check Villagers for the book and trade them emeralds for the book when they have it.
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