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.
This will require you to search deeper within the oceans for these creatures, as they are harder to find than regular squids. You can help this by stocking up on either respiration potion or enchanting a helmet that has at least two or three respirations.
Either one of these will assist you in your search for squids in deep water and ocean biomes. Why would you want to?
If you are using glow squids to make item signs or other signs, they can be very helpful.
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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.
However, you can only get three glow squid items from the glow squid. We recommend that you purchase a weapon with a looting spell to increase your chances of getting glow-ink sacs.
Your weapon will require at least looting III. If you kill a Squid with it, the drop rate will go up to six.