Ender Dragon

The Ender Dragon is the first official boss mob to appear in Minecraft (with the second being the Wither). It only naturally spawns in The End. This mob uses the dragon model Notch created, but utilizes a texture more reminiscent of an Enderman, being black and scaly with purple eyes. It is widely acknowledged as the main antagonist of the game, having a bar of health at the top of the screen when in the world.

Appearance
The Ender Dragon is a large, black dragon with purple eyes and four big, black legs with three toes on each one. It is by far the largest mob in the game, about 20 times as long as a pig, and is made of 61 cuboids, more than any other model. It has a few light gray features, such as the wings and various other parts of its body. Similar to endermen and spiders, the Ender Dragon's eyes are visible through darkness, so you can see it coming from anywhere in the End.

Behavior
The Ender Dragon will destroy any blocks it comes into contact with, except obsidian, end stone, bedrock, command blocks and barriers although they do not appear in the End. Instead of destroying them, the Ender Dragon passes through them. When hit, an Ender Dragon makes roaring, growling and snarling noises. The flapping of its wings can also be heard as the dragon moves. Unlike Endermen, Ender Dragons don't take damage from water.

The Ender Dragon has a purple health bar that appears at the top of the player's screen. This bar indicates the remaining health of the resident Ender Dragon. Each End dimension houses a single Ender Dragon whose health is periodically healed by nearby Ender Crystals. Destroying an Ender Crystal while the Ender Dragon is being healed by it (indicated by a series of circles appearing between the Ender Crystal and the Ender Dragon) will cause the Ender Dragon to take additional damage instead of being healed.

Once killed, the Ender Dragon will appear to have beams of light spontaneously erupting from its body. It will then explode, dropping enough experience to bring a player from no experience to level 78 (12000 - 10 drops of 1000 experience, one drop of 2000 experience).

It will also spawn an exit portal with a Dragon Egg on top. Entering the portal will activate a text cutscene that lasts for an average of 8 minutes, 30 seconds. After the cutscene, the player will be teleported to their spawn point/Bed in The Overworld. The cutscene can be skipped by pressing the key, (B on Xbox 360 and O on PS3), and will instantly send the player to their spawn point/Bed in The Overworld. The player may return to the End after defeating the Ender Dragon, however there will be no new dragon.

When spawned in the Overworld, using the new /summon command, as of snapshot 13w38c, the Ender Dragon exhibits the same behavior when killed, however, the End Portal spawned leads to the End, where another Ender Dragon still resides, and no text cutscene plays. Also, it seems to orbit around the origin (0 x 0) when not attacking a player. Command: /summon EnderDragon.

The Ender Dragon will only attack the player normally, however it can accidentally attack an Enderman causing it to turn hostile towards the Ender Dragon, chase after it, and attack it, akin to when it is attacked by a player.

On both the Xbox 360 and the PlayStation 3 Editions, the Ender Dragon's behavior is slightly different. While flying, the Ender Dragon fires projectiles at the player. After flying for approximately 30 seconds, the Ender Dragon will come down and hover over the unfinished bedrock portal, and remain there for another 30 seconds. The Ender Dragon will spew out "Ender acid" on nearby players, which deals damage. Players may continually strike it with a weapon at this time. The Ender Dragon also fights Endermen during this time, implying the reason for returning to the "nest" is to stop the growing clusters of Endermen from stealing the egg.

Enderdragon Strategy
The Ender Dragon's most common strategy is to attempt to charge the character. The Ender Dragon can also be healed by Ender Crystals as mentioned before and will not be damaged by water, fire, or lava, unlike the Endermen.

Anti-Enderdragon Strategy
The most common and easiest strategy to defeat the Ender Dragon is to destroy all of the Ender Crystals before attempting to fight the Ender Dragon, as any damage done to the dragon can be quickly undone by the crystals.

After receiving damage, the Ender Dragon will fly away a small distance before charging again. Make usage of this to run back. It's recommended using the bow to damage the Ender Dragon from really long distances, because it will always fly away every time it attempts to attack you.

When the Ender Dragon charges the player, it is directly facing the player. This gives the player a good chance of attacking its head to deal the most damage; attacks that hit any other part of its body cause only one-quarter (plus one point) of their normal damage. If the player decides to attack it, he/she will have less time to try to avoid its attack. The impact of the Ender Dragon's body and wings cause damage to the player, as well as massive knockback. Diamond armor and weapons (preferably all enchanted) are recommended. Because of the Ender Dragon's speed and flight, projectiles are favored over melee approaches. The Ender Dragon's immense health and evasive nature require a large ammunition stockpile or an Infinity-enchanted bow. At least 2 full stacks of arrows are recommended since most will miss.

Lava is useless, as it is immune to fire damage. Water is also useless, as it will take no damage from water and will destroy the source block; however, it can be used to make a "safe zone" which Endermen will teleport out of. Knockback enchantments are useless unless the enchantment is on grade 8 or higher (this is possible in SMP with modifications). Snowballs have the potential to stun-lock an Ender Dragon as its recovery time is slower than the firing rate of snowballs. Due to a quirk of how it reduces damage taken, snowballs and other projectiles, such as Ender Pearls and Eggs, that normally cause no damage to entities will deal one point of damage to the Ender Dragon. Beds, which explode in the End, can be detonated when the Ender Dragon is nearby, causing considerable damage to it. Since the Ender Dragon only takes damage from players and explosions, Snow and Iron Golems are completely ineffective and rarely attack the dragon if at all. Similarly, negative splash potions have no effect on the Ender Dragon.

To avoid fighting the Endermen, do not look at them with your crosshair. Alternatively, equip a pumpkin in the head gear slot which covers up your cross hair allowing you to look where ever you want. This strategy's downfall is that it obstructs your vision making it hard to keep an eye on the dragon. Invisibility will also prevent aggression by Endermen. However, since you have to remove your armor in order for invisibility to be effective, and the Ender Dragon itself ignores invisibility, this is a dangerous strategy. A large force of snow golems can serve as a distraction for the surrounding endermen: the sheer amount of snowballs fired at them will make them teleport constantly, lessening their threat potential. The Ender Dragon may kill or knock back many of them, so a large army and replacement golems are recommended if this strategy is used. Iron golems can also be used in the same way, and as a bonus actually kill endermen instead of making them teleport; however, they are much more expensive and hard to replace if knocked back or killed.

Console Edition
As of the TU9 Update for Xbox 360, the Ender Dragon spits out "Ender Acid". The Ender Acid is purple, much like the particles around the Enderman. They also fire a type of Acid Ball similar to Ghasts, Blazes and Fire Charges, but with a more purple texture, which cannot be deflected. Like the PC version, they can also destroy/grief blocks placed by the player.

Also, instead of the portal being spawned underneath the Ender Dragon's death, it is spawned in the middle of the island as soon as you enter the End. However until the Ender Dragon is defeated, it will remain deactivated, and the Dragon Egg will not be on its podium. Until it has been killed, this is used by the Ender Dragon as a nest, where it will hover over it and attack the player with "ender acid".

One final difference between the Console and PC versions is that some of the Obsidian Pillars have iron bars surrounding the crystal. This prevents the player from shooting it from a distance with a bow, ensuring the player has to climb some of the Pillars.

Video
Note: The video states the Ender Dragon is the only boss. This is outdated, as the video was made before the Wither was implemented.

Trivia

 * Using the command will kill an Ender Dragon in one shot with an Iron sword. It doesn't matter if it is healing itself with a crystal.
 * Name Tags cannot be put on an Ender Dragon.
 * In the Console Edition, Ender Dragons cannot go through Bedrock or Obsidian, meaning if you were to make a house out of bedrock or obsidian, the Ender Dragon would not be able to destroy anything placed inside.
 * Contrary to popular belief, the Ender Dragon cannot be harmed by any mob other than a player or explosions. Therefore, the dragon will never purposely attack another mob, including a Wither.
 * The Xbox avatar item 'Ender Dragon Pet' has the description 'A cuter, friendlier version of his bigger, less playful Minecraft sister.'- revealing that the Ender Dragon is female. (Note: Quite a lot of people already knew this, noting that only females can lay eggs.)
 * However, some people confuses the Ender Dragon as a male because of the deep voice and an Enderman colour.
 * The Ender Dragon has its own separate mob folder containing separate designs: the old gray skin and the newer black skin.
 * The Ender Dragon flies at 10 times the player's normal walking speed.
 * An Ender Dragon's attack can cause Endermen to chase after it and attempt to attack it to no avail, should they survive the devastating attack. This also works with blazes, wolves, and zombie pigmen.
 * The Ender Dragon's hitbox is larger than the Ender Dragon itself, causing players to be pushed away from it.
 * You can get a plain white spawn egg that reads Spawn Ender Dragon by using the command . However, when you try to spawn it, you cannot and it does not really work as anything.
 * As long as the Ender Dragon is alive, the space texture of End Portals, as well as the player's view in the End, will have a slight multicolored static overlay to it.
 * If you go beyond the "island" in the End, the Ender Dragon will constantly attack you instead of circling around before striking.
 * If the Ender Dragon is killed when there is no solid ground below, the portal to the Overworld will appear approximately where it died.
 * If you spawn the Ender Dragon in a world and turn the difficulty to peaceful, the Dragon will stay and not disappear, but will not be able to hurt the player.
 * The Ender Dragon can't destroy Minecarts with Chests, making them a good alternative to store your items while in the End.
 * If you set a Superflat world to the End biome (9), and go to 0,0, the Ender Dragon will be there.
 * If you kill a spawned Ender Dragon in the over world, it will drop a portal to the real End. There will be a separate Ender Dragon in the real End. Of course the Dragon only spawns in the over world using or the previous trick.
 * Ender Dragon makes the same crackling sound as a firework when it dies.
 * The Ender Dragon from the TU9 update is the only version of it that actually has a working projectile.
 * Ender Dragons can push other Ender Dragons around.
 * Ironically, the Ender Dragon can destroy End Portal Frames (including those with Ender Eyes inserted).
 * Ender Dragons will attempt to attack players in creative mode, though this has no effect as creative players are invincible other than dying from the void or the /kill command. This makes the Ender Dragon the only mob in the game that is still hostile towards the player in creative mode.
 * When spawned in the overworld using the /summon command, players in creative mode at a certain height forces Ender Dragons to flap their wings wildly.

Notch-related trivia

 * The name "Ender Dragon" was first made known through a tweet by Notch reading "raqreqentba", which could be decoded using the ROT13 cypher, translating to "enderdragon".
 * On Reddit, Notch referred to the Ender Dragon as a she, and suggested her name to be "Jean?" in the same manner he called the Player "Steve?".
 * Notch joked about how Minecraft was "going next gen" when deadmau5 mentioned this.
 * Before it was textured, Notch reported that he was afraid to texture it as it was a complicated model. In the end, the dragon model was so complex Notch stated that he gave up making the texture manually and wrote a texture packer tool to aid him in adding the texture to the model. Notch also uploaded the code for the tool so others could use the pack.
 * In terms of how difficult the Ender Dragon is to defeat, Notch tweeted that his design guideline for the dragon is "[If] I can beat it at all, it's too easy."
 * Notch has uploaded a video showing why Ender Dragons will not spawn in the main world, as they would destroy any block they come into contact with.
 * On Reddit, Notch explained why Ender Dragons destroy matter.