Thorns is a defensive armor enchantment in Minecraft that deals retaliatory damage to attackers while increasing armor durability consumption.
Players can obtain Thorns from an enchanting table — it is an ordinary enchantment, not a treasure one — and also through trading with librarian villagers, fishing for enchanted books, or discovering it in structure loot from mineshafts, strongholds, desert pyramids, ocean ruins, end cities, bastion remnants, and various dungeon chests. Thorns III is the exception: a table cannot roll it at all, so the top level comes from combining two Thorns II books or armor pieces on an anvil, or straight out of loot or a librarian's trade.
Thorns provides a 15% chance per level to deal 1-5 damage to attackers, with Thorns III offering a 45% chance to retaliate against any direct attack including melee, arrows, and projectiles. Multiple armor pieces with Thorns stack independently. However, the enchantment increases armor durability damage by 2 additional points when activated.
The enchantment works against most attacks, though not a warden's sonic boom, making it effective for players seeking aggressive defensive capabilities in combat situations and mob farming operations.