Enderman

Endermen are three-block-high mobs that spawn fairly uncommonly in the Overworld at light levels of 7 or less, and they densely populate The End. Endermen are neutral, but they will turn hostile when provoked. They are known for their spooky presentation, their unique abilities to pick up blocks and teleport, their vulnerability to water, and the odd noises they make.

Endermen are the main source of Ender Pearls (the only other being stronghold chests), which are useful both in their own right and as a crafting ingredient for Eyes of Ender, which are necessary to reach The End.

Endermen can be provoked via an attack or by simply looking at them (placing the crosshairs on their upper bodies from up to 64 blocks away). When provoked, Endermen stand still, stare at the player with trembling, gaping mouths, and emit a long, loud, unsettling noise, before teleporting towards the player to attack.

Endermen frequently spawn in The End, their home world, but still require a light level of seven or less in order to spawn. They will also spawn in the Overworld, although about 5-10 times more rarely than other mobs like Zombies, Skeletons and Creepers. They spawn in pairs, and can be seen at night in groups of up to five. However, they will very often teleport away carelessly, so you will most likely see only one or two at a time.

Appearance
Endermen have long limbs, thin bodies, black skin, glowing purple eyes, and emit the signature purple Ender particle effect (like Ender Chests, Endermites, Nether Portals and Eyes of Ender). They are often seen holding blocks.

Behavior
Endermen always initially spawn in pairs, but will often appear individually or in larger groups due to random teleportation. Endermen make strange noises and will mostly teleport away when they take damage. They take damage from contact with water or rain, upon which they will immediately teleport in search of dry areas. In rain they can be seen teleporting rapidly as they search for shelter, but can often die from rain damage. Taking damage from an attacking player will cause them to teleport behind the player and attempt an attack, unless the player is looking at the Enderman's legs, which will usually prevent teleportation.

Endermen don't attack unless provoked, although looking at their bodies or upper legs from up to 64 blocks away is considered provocation. Staring at an Enderman will cause the player to hear a lengthy, loud, threatening sound. When provoked, Endermen will open their mouths and shake with rage. Staring at their torso will stop them from moving, and you can approach and attack, at which point they will teleport behind you. If an aggravated Enderman is hit by another mob, for example, an Iron Golem or the Ender Dragon, it will cease attacking the player.

Endermen have a unique ability to pick up certain block types and move them around, which they generally spend their time doing while neutral. They can also step up one full block without having to jump.

Endermen will continue chasing a player until they are either killed, sustain several hits, or become distracted by exterior elements like rain, fire, or sun; Endermen are likely to teleport away to underground locations at day break.

In Creative mode, Endermen will not get provoked if you look at them, nor will they become provoked if hit.

Endermen can't be provoked by players looking through transparent blocks like glass/glass panes, from within a boat or minecart, or wearing a pumpkin on their head.

Endermen are also able to climb ladders, but only when forced to, as their AI does not handle ladders in a special way.

Teleportation
Endermen always attempt to teleport when attacked or taking other damage, such as from water. Most ordinary melee attacks are successful (such as with a sword), but are followed by an immediate teleport, generally to a point a few blocks behind the attacking player. Endermen cannot be attacked with projectile weapons in the PC version, as they will always teleport away just before being hit (in the Xbox 360 version, it is possible to hit an Enderman with a projectile by arcing a shot onto the Enderman without placing the crosshairs on them directly). They also cannot be attacked with Splash Potions of Harming, as they will similarly teleport away before the potion impacts any nearby surface. Splash potions of Poison, however, do work and the Enderman will not become hostile unless hit directly or looked at. In other words you can splash an Enderman with a poison potion and wait for its health to get down to a couple of hearts and then kill it.

When teleporting, Endermen search for an air block within 32m (along each axis); if there is a solid block below that air block, they can teleport to it regardless of the downward distance. An Enderman can teleport onto nearly any solid block, exceptions being blocks directly beneath water or lava or blocks with less than 3 vertical spaces above. Endermen will not teleport into water or lava.

An Enderman cannot teleport when it is in a minecart, though in rain and water it will attempt to do so, although it will always teleport back into the minecart repeatedly until death.

Endermen will not teleport in the daytime while on soul sand unless they are damaged.

Moving blocks
Endermen will only pick up and move certain blocks, regardless of whether they were natural or placed by the player. They will pick up blocks horizontally and vertically nearby, within 3 layers.

Endermen will not drop the block they are holding when enraged or slain. It will simply disappear.

Endermen can only pick up the following blocks:

Endermen cannot pick up entities, such as boats, minecarts, primed TNT, and mobs.

Enderman can create iron or snow golems due to their ability to pick up and place pumpkins anywhere they want (on top of an l shaped snow block formation or T shaped iron block formation.) However, this is extremely rare because Endermen place blocks completely randomly and can only pick up the pumpkin.

Because Endermen possess the ability to move blocks, they can cause damage to the natural environment and in some cases player-built structures. They can also allow fenced animals to jump out by placing blocks adjacent to fences. Their block handling is not purposeful, but they may randomly breach walls and the like.

In the Overworld, signs of Enderman activity will become apparent in frequently loaded chunks in the form of misplaced blocks. In desert areas, Endermen may also propagate cacti by removing blocks and placing them on fresh sand, gradually increasing the population of cacti in frequently loaded deserts.

Endermen do not spawn in well-lit areas, but they may wander or teleport into lit areas from adjacent dark ones, particularly if rain or water causes them to teleport. It can be risky to stay awake at night, as an Enderman can teleport into your house. This is more apparent in large buildings, where rain may cause the building to be invaded by multiple Endermen seeking shelter. Therefore, lighting your structures with torches is not a guaranteed defense. However, they will not teleport into areas where they won't fit, so two-block high ceilings will keep them out.

One can summon an Enderman holding any block using {carried:Block ID} NBT tag.

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 the Xbox 360 Edition, the Enderman is re-skinned to look like the Slenderman.
 * If an Enderman is in his aggressive state, you can prevent him from walking/going anywhere if you stare at him (you can freeze the enderman as long as your cursor remains on him). However, if attacked in this state, the enderman may teleport away.
 * The Enderman seems to use a re-colored version of the player's face texture, much like blazes, zombies, and skeletons.
 * The exact size of an Enderman is 0.6x0.6x2.9 blocks(1.9x1.9x9.5 feet).
 * Enderman sounds seem to be reverse audios:
 * the "idle1" sound is a reversed “here”
 * the "idle2" sound is a reversed "hiya"
 * the "idle3" sound is a down-pitched “whats up?” or "this way!"
 * the "idle4" sound is a down-pitched reversed "forever!"
 * the "idle5" sound is a reversed "uh oh!"
 * Even in an aggressive state, they can still pick up blocks, which at times makes it look like they are tearing through walls to reach the player. However, they do not intentionally pick up blocks in order to reach the player.
 * If a Mob Spawner is tweaked to spawn Endermen, the model inside will have its head jutting out the top of the frame. In Pocket Edition, however, the model is shrunk to fit within the block.
 * The purple particles that Endermen emit are hard-coded into the game, so they cannot be re-textured without mods.
 * Amusingly, if an Enderman is set on fire, they may try to put it out by teleporting into water, and therefore committing 'suicide', because they take damage from it. However they usually teleport back out, fresh and clean and ready to fight again.
 * Using spawn eggs, Enderman continuously spawned into lava will humorously teleport - in the Nether, they will often teleport in circles for lack of room due to the lava oceans.
 * Amusingly enough, if an Enderman is caught in rain, it will continuously teleport in random directions. Players can sometimes, during rain, see Endermen teleport in front of them quickly and teleport off the moment they take damage.
 * If you throw a Potion of Invisibility to an Enderman, the Enderman will be invisible, but you can still see the eyes. This is because the eyes, like spiders, are in a separate texture file.
 * In the End, an invisible Enderman at a distance will become visible as a pale purple figure.
 * If you go to sleep in a bed it is possible for an Enderman to teleport on it and knock you off. You will still continue to go to sleep as if you were in a bed.
 * Endermen can be hit by arrows in the Console Edition. Although they appear to teleport away half a second before the arrow hits they will take damage after the teleportation, and if it was a flaming arrow the Enderman will be on fire. Shooting one in Pocket Edition will play the arrow vibration effect, implying it got hit.
 * In PC and Pocket Edition, they cannot be hit with arrows. When arrows are shot at an Enderman that cannot teleport anywhere, the arrows simply bounce off.  Endermen will not catch fire from flaming arrows.
 * Endermen originate from the End, yet they are unable to pick up and move the End Stone of which that world is made.
 * On the rare occasion an Enderman creates a golem, it may cause it to attack the Enderman as soon as it places the pumpkin.
 * Switching to spectator mode and taking an Enderman's camera adds the invert shader, suggesting that they see The End as an island of blue cobblestone (because end stone is a yellowish inversion of cobblestone) in a white sky, with white pillars, white Endermen with green eyes and a white Ender Dragon.
 * The collective noun for a group of Endermen is "a haunting of Endermen", as stated by Dinnerbone.
 * Endermen are the only mobs that pick up blocks in placed form.
 * In Pocket Edition, Endermen are attracted to water, effectively making them suicidal.
 * In 1.8 an Enderman chasing after a player standing in water in a lake or river may teleport upon taking damage from the water and move towards it again, repeatedly taking damage whilst trying to reach the player.

Beta 1.8+
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