Piglin

Piglins are neutral mobs that spawn in the Nether. They are equipped with crossbows or golden swords. They are hostile towards players but become neutral if the player wears golden armor.

Spawning
Piglins spawn commonly in groups of 1–3 in crimson forest and uncommonly in the nether wastes biomes. Each piglin has a 25% chance of being a baby.

Adult piglins spawn with either golden sword or crossbow and occasionally with golden armor. Baby piglins spawn without any equipment.

Drops
Piglins have 8.5% chance of dropping their naturally-spawned equipment and drop it with random durability. Each level of Looting increase the chance by 1 percentage point (11.5% chance with Looting III).

Any picked-up equipment or other picked items have 100% chance of dropping and drop without changing the damage that has accumulated on it.

Experience
Piglins drop 5 experience if killed by player or tamed wolf.

Behavior
Piglins are naturally hostile to the player, unless the player wears at least one piece of gold armor. If so, they will become neutral but will attack player if the player attacks first, opens chest, trapped chest, ender chest, barrel or shulker box near the piglins or mine gold block near them.

Piglins attack wither skeletons, but only if there is at least one another piglin nearby. They also attack adult hoglins when they're hungry.

Baby piglins are passive and never attack anything.

When attacking, an adult piglin with a crossbow will shoot arrows every 2 seconds, and walk backwards (stopping if at the edge of a drop) as soon as the enemy is close. Unlike bow-armed mobs, they will not strafe from left to right while doing this. Piglins with swords and other equipable items just rush at a player.

Piglins will willingly downgrade to golden armor if they are wearing higher tier armor, or armor that has higher durability than gold, such as iron, chainmail, diamond, and netherite armor.

When in the Overworld, piglins will transform into zombie pigmen after about 20 seconds. When they transform, they will lose all their armor and held items and will be given a golden sword. Upon transformation, the newly spawned zombie pigman will have the Nausea effect for about 10 seconds.

Piglins are scared by zombie pigmen, soul fire, soul fire torches and soul fire lanterns. Piglins are capable of opening doors.

Piglins cannot swim in water, and will drown. However, the conversion to zombie pigmen always takes place before drowning can begin.

Picking up items
Any piglin can pick up and equip any gold related item, regardless of their ability to pick up other items. While doing so, Piglins will "contemplate" at the specific item by looking at it for a mere moment. Piglins that currently have crossbows can trade those out in order to hold any other gold related item instead (apart from ingots, which are consumed in bartering), even if it is not actually a weapon, and drop their crossbow on the floor.

Piglins have eight hidden inventory slots. Baby piglins can pick up any item and will attemt to, often stealing from player. Adult piglins can pick up any golden item and porkchop. Golden apples, their enchanted variant, golden carrot and porkchop are the only items piglins will store in their inventories. Player can use the command to put an arbitrary item into a piglin's inventory.

Trivia

 * Piglins could be seen as reincarnation of Pigman, mob that originally was supposed to inhabit villages but was scrapped. Piglins share this pigman theme with Zombie Pigmans.
 * Piglins receive damage from both fire and lava, as do hoglins.
 * Their attack strength varies a lot in all difficulties.
 * They are one of only three mobs in the game that can willingly give items to another player (through bartering), the others being villagers and wandering traders (through trading).
 * Despite unlocking the "Monsters Hunted" or "Monster Hunter" advancement when killing them, they do not despawn in Peaceful difficulty.
 * Piglins cannot ride on other entities.
 * Piglins are also one of only two mobs that can wield crossbows, the other being pillagers.