Piercing is a quality enchantment used on crossbows in Minecraft. It allows players to fire arrows that can pass through entities and shields.
Piercing can be applied by using enchanting tables or combining enchanted crossbows via the anvil block. Players can also apply enchanted books to crossbows with an anvil.
Regardless of how players acquire Piercing, the enchantment is an excellent aid in combat, especially when using a crossbow. However, it does have limitations and incompatibilities that are worth keeping in mind.
Minecraft's Piercing enchantment breakdown
Overall, Piercing has a total of four enchantment levels. Each level increases the number of entities that a crossbow can fire a projectile through (for a total entity count of the enchantment level +1, meaning five in vanilla Minecraft). Even though the projectiles can pass through multiple entities, including shields, they can still be reclaimed once they hit the ground.
This effectively makes Piercing an offshoot of the bow enchantment Infinity. As long as players fire their crossbow arrows through targets and into the ground, they can be reclaimed, allowing for a theoretically limitless supply of arrows. However, arrows can't be reclaimed if they pass through targets and fall into something like lava or the void.
Furthermore, Piercing has no effect on firework rockets fired from crossbows despite other enchantments influencing them.
If an enemy is using a shield, a Piercing-enchanted arrow will still strike through the shield regardless of whether it is being used to defend.
One of Piercing's main drawbacks is that it cannot be combined with the Multishot enchantment by default. However, if the enchantments are combined via the use of commands, the two will operate as expected. Each arrow fired from Multishot will possess the appropriate Piercing enchantment.
If Minecraft players create a crossbow utilizing both Multishot and Piercing, they can effectively create a powerful weapon capable of skewering entire groups of enemies.
However, if players aren't willing to enable cheats and use commands to create the weapon, they'll have to stick to using the vanilla crossbow enchantments. In this case, Multishot and Piercing are mutually exclusive.