Glow squids are one of the new mobs being introduced in the new update Caves and Cliffs to Minecraft, and you can find these new variants of squids deep underwater.
You will also need to search deep within oceans for these creatures as they will be harder to find than the normal squids in the game. We recommend stocking up on either respiration potions or enchanting a helmet with at least respiration two or three to help you with this.
Overall, either one will help you with searching ocean biomes and deep underwater for these squids. But why would you even want to?
Well, glow squids actually can be quite useful if you are playing around with item signs or regular signs in the game.
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The reason is that glow squids have special ink called glow ink sacs that can be used to craft item signs and regular signs that either make text or the item glow.
That being said, the glow squid can drop up to three of these things, so if you really want to boost your chances of getting glow ink sacs, we recommend getting yourself a weapon with a looting enchantment.
You will need at least looting III on your weapon, and if you kill a squid with it, you will increase the drop rate to six.