Enderman

"This long-limbed, purple-eyed, darker-than-night mob is not one you want to get into a staring contest with. Usually seen in the Nether and The End, its presence is rare in the Overworld. Rarer still - players who've made eye contact with it and then survived to tell the tale."

- Tom Stone

Endermen are black, neutral mobs from the End that have the ability to teleport.

Spawning
Endermen spawn on solid blocks at light level 7 or less. They spawn commonly in the End in packs (or "hauntings") of 4. In the Overworld they spawn in groups of 1-4 and are rarer than most other mobs. In the Nether they spawn in groups of 4 and are even rarer.

Drops
Endermen drop:
 * 0–1 s (or up to 4 with the Looting enchantment)
 * 5 experience orbs when killed by a player or a tamed wolf.
 * Endermen holding a block will drop that block. (See here for more information)

Behavior
"This mob becomes hostile if you attack it (easily avoided) or if you just gaze upon it (oh dear). Considering it can run at you, teleport around the world, and chase you with obsessive persistence just because you looked at it the wrong way, we'll give you some friendly advice: don't get caught staring. You should get that tattooed on the inside of your eyelids to help you remember. Thank us later."

- Tom Stone

Endermen do not attack unless provoked by a player or mob attacking them or looking at their body or head from up to 64 blocks away. When provoked, endermen will open their mouths, shake with rage, and frequently make screaming sounds; when provoked by being stared at, they will also make a lengthy, loud, threatening sound and will run towards the player to attack. If an aggravated enderman is hit by another player or mob, it will cease attacking the victim.

They can also step up one full block without having to jump.

Endermen are damaged by water, splash water bottles and rain, and will teleport away when they take damage from any of these. However, endermen do not take damage while standing in a filled cauldron. They will also teleport if they take suffocation, projectile, fire or lava damage, as well as damage from poison or the wither effect.

Endermen will continue chasing the player until they are either killed, sustain several hits, or become distracted by exterior elements like rain, fire, or sun; they are likely to teleport away to underground locations, such as caves, mineshafts, and strongholds, at day break. If the player sleeps in a bed, it is possible for an enderman to teleport on it and knock them off, however the player will continue sleeping.

Endermen cannot be provoked by players looking through transparent blocks or wearing a pumpkin on their head. However, they can become aggravated by a player in a minecart from some angles.

Endermen will attempt to kill endermites, provided they were spawned from ender pearls and there is no nearby player in Survival or Adventure mode. If the player is close enough to an endermite, endermen focus on the player instead of the endermite. Endermen can spot endermites from a distance of 64 blocks, similar to being provoked by being stared at.

When under the Invisibility effect, the enderman's body will disappear, but its eyes will still be visible.

Teleportation
When teleporting, for each attempt a random destination is chosen within 32 blocks along each axis (i.e. a 64×64×64 cuboid centered on the current position). It then seeks downwards (regardless of distance) from the chosen destination until the block below is made of a movement-blocking material. The teleportation attempt will succeed to that location as long as no liquid or solid blocks prevent them from standing there. Thus endermen typically need at least three non-solid blocks above the destination to successfully teleport. Exceptions are carpet that is not above a block made of a movement-blocking material and snow layers stacked 10 deep or more, as their materials are not flagged as blocking movement even though the blocks themselves do so.

Endermen always attempt to teleport upon taking damage, such as from water. Most ordinary melee attacks are successful, but are usually followed by an immediate teleport to a few blocks behind the attacking player. When directly attacked by the player, enderman have a chance not to open their mouths. Endermen cannot normally be attacked with projectiles in Java Edition (including splash potions of harming), as they will always teleport away just before being hit. However, they will not teleport if positive potions are thrown at them, including splash potions of regeneration and strength, and will not teleport away from poison potions either. A splash water bottle will deal damage to an enderman if it is caught in its radius of effect. If all available blocks within teleport distance are removed or unable to be transported to, it is possible to hit endermen in Java Edition with a projectile, though arrows tend to bounce off dealing no damage on occasion. However, in the Legacy Console Editions, it is possible to hit an enderman with a projectile by arcing a shot onto the enderman without placing the crosshairs on them directly. When teleporting due to damage, an enderman will make up to 64 attempts to teleport.

An enderman cannot teleport while it is in a minecart or boat, though in rain and water it will attempt to do so, always teleporting back repeatedly until death.

Endermen will not teleport in the daytime while on soul sand unless they are damaged. They will also not teleport if attacked on their legs or by wolves, as wolves attack at the legs. Endermen also hardly teleport when combating other mobs like iron golems.

It is possible for an enderman to teleport at death. In Java Edition and Legacy Console Edition, the ender pearl should drop as soon as the enderman dies, but the experience orbs only appear when the enderman's body disappears. Because of this, it's possible to slay an enderman, pick up the pearl at the point where the enderman received the killing blow, and find the experience in the location the enderman teleported to. In Bedrock Edition, the ender pearl is dropped together with the experience, when the enderman's body disappears. This can make it even harder for the player to gather loot.

Moving blocks
Endermen have a unique ability to pick up certain block types and move them around. They will pick up blocks in a 4×4×3 region horizontally centered on the enderman and vertically at the same level as the enderman itself. Endermen drop the block they are holding on death as an item, however they do not visually let go of the block when dying.

Endermen can only pick up the following blocks: Java/'''Bedrock Editions only:
 * All editions
 * All editions
 * All editions
 * All editions
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 * All editions
 * All editions
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 * All editions
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 * All editions
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 * All editions

When carrying a block, the enderman may randomly place it, in a 2×2×2 region horizontally centered on the enderman and vertically at the same level as the enderman itself, if the target location is air with a non-air block beneath and the block is allowed to be placed at the target location.

While endermen may breach walls, bridge fences, break redstone circuitry, and even construct golems by removing or placing blocks, such actions are entirely random and not purposeful.

One can summon an enderman holding any block (including the ones not listed above) using the  NBT tag.

Data values
Endermen have entity data associated with them that contain various properties of the mob. Their entity ID is.

Trivia

 * Notch claimed in public that the enderman is a “subtle” reference to “the Slenderman”, a similar looking monster with a similar name. Given the later development of the End, it is possible he already had the name in mind, and did not choose it because of the Reddit thread in which their name was revealed.
 * In the Halloween texture pack for Legacy Console Edition, the enderman is re-skinned to look like the Slenderman.
 * Endermen sounds seem to be reverse audios:
 * The "idle1" sound is a reversed “here”
 * The "idle2" sound is a reversed “hey”
 * The "idle3" sound is a down-pitched “what’s up?” or “this way!”
 * The "idle4" sound is a down-pitched reversed “forever!”
 * The "idle5" sound is a reversed “uh oh!”
 * The collective noun for a group of endermen is “a haunting of endermen”, as stated by Dinnerbone.
 * Additionally, in the third episode of Minecraft: Story Mode, The Last Place You Look, your character is given the option to correct the grammar of several other characters by specifying that the collective noun for a group of endermen is "a haunting of endermen," supporting Dinnerbone's statement.
 * Switching to spectator mode and taking an enderman’s point of view adds a shader that inverts colors, suggesting that they see the End as an island of blue cobblestone (because end stone is a yellowish version of cobblestone with inverted colors) in a white sky, with white pillars, white endermen with green eyes and a white ender dragon, also with green eyes.
 * If a player or mob is at least 64 to 72 blocks (4-4.5 chunks) away from an aggravated enderman, it will likely teleport directly to the victim.
 * Although they are neutral, endermen will keep any nearby players from sleeping on a bed at night.
 * If the ender dragon hits a group of endermen, the endermen will attempt to retaliate.
 * The texture for an enderman's eyes is located in a different texture file than the body, allowing their eyes to glow.
 * If directly attacked by a player (one hit only), endermen have a chance not to open their mouths.
 * Unlike any other mob, endermen can only be attacked melee or with splash water bottles, as other methods of attack will simply cause them to teleport away.
 * The enderman is the only mob that can naturally spawn in all dimensions.
 * The enderman teleportation sound also plays when a player teleports using an ender pearl or chorus fruit.