Ender Dragon

The Ender Dragon is the first official boss mob to appear in Minecraft. 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. Like other dragons, the Enderdragon will have 6 limbs; consisting of 2 wings, 2 legs and 2 arms.

Strategy
Upon entering The End, a Boss health bar appears at the top of the player's screen. This bar indicates the remaining health of the resident Enderdragon. Each The End houses a single Enderdragon who is periodically charged by nearby Ender Crystals. These crystals can be found at the summit of Obsidian pillars which dot the otherwise flat landscape. The Ender Crystals' healing effect can reverse hard won damage quite quickly and it is therefore recommended that they be destroyed before the player engages the Enderdragon. Wearing full diamond armor will make the enderdragon unable to hurt you, and will simply push you around.

Destroying an Ender Crystal while the Enderdragon is being charged by it (indicated by a series of circles appearing between the Ender Crystal and the Enderdragon) will cause the Enderdragon to take additional damage instead of healing.

The Enderdragon will flee when looked at, but will otherwise fly directly at the player. The Enderdragon will moreover destroy any block it comes into contact with excepting Obsidian, End Stone and Ender Crystals which makes TNT strategies difficult if not impossible to successfully execute. The Enderdragon will also phase through obsidian. Due to the Enderdragon's speed, flight, skittish behavior, and tendency to explode when defeated, projectiles are favored over melee approaches. The Enderdragon's immense health and evasive nature necessitate a large ammunition stockpile. Snowballs have the potential to stun lock an Enderdragon as they both fire faster than its hit recovery time and inflict damage. Once killed the Enderdragon will detonate, drop a massive amount of experience, and spawn a Dragon Egg on top of an End Portal made of Bedrock. On the second block up, two Torches are placed on either side. Entering the portal will activate an eight minute text cutscene which acts as the end of Minecraft. The player will be teleported to their spawn point at the end of the cutscene.

History
Originally, dragons were a possible planned mobs hinted at by Notch during the Spider Jockey update. He also mentioned that dragon lairs may be an addition. They remained a potential work-in-progress until the Enderdragon was announced. A videoshowing the final boss defeated in Creative mode.

Notch has, in the past, stated that if dragons are added, they will not be able to be mounted because it would put pressure on servers in SMP.

In September 2011 Notch stated that "dragons will be added eventually".

On October 7th 2011 Notch revealed the existence of the Enderdragon.

On October 10th 2011 Notch released a video showing a small clip of The End which also shows the Enderdragon fly into the top of the frame. 

On October 11th 2011 A player named stropping_notch asked Jeb if Dragon riding is an idea, to which he replied it is. It is not clear whether this means it is an idea under consideration or not, however, or whether it would apply to the red Dragons or the Enderdragon.

On October 12th 2011, in a Reddit post Notch also said, "They will be different dragons. The Enderdragon will probably become larger, and the ones in the main world will be this size, won't go through terrain, and will be red because dragons are red."

On October 12th 2011, in a twitter post Notch also said: "Dragons have 6 limbs" Which would consist of 2 wings, 2 legs and 2 arms.

On October 13th 2011, Beta 1.9 Pre-release 4 was released along with The End. The Enderdragon exists in the code, mostly functional, however the dragon had not been enabled ingame yet. A community-made mod allows players to spawn Enderdragons by parrying with a golden sword.

On October 27th 2011, Beta 1.9 Pre-release 5 was released and Enderdragons could finally be hurt. They still do not seem to appear naturally in The End and need mods or a mob-spawner to be brought into the game. However, when slain, it has a very distinct death animation: it will rise upwards, emit purple beams of light from its body while the body itself disappears pixel by pixel, until it's all gone, and the lights fade away. They dropped a block of Obsidian along with their large amount of experience. Their bodies also deflected arrows.

On November 11 2011, Beta 1.9 Pre-release 6 was released and Enderdragons could finally spawn in The End.

Bugs

 * On SMP when player is killed by Enderdragon. This message appears: *playername* was slain by entity.EnderDragon.name.
 * If the game crashes while in The End, more Enderdragons may spawn.

Trivia

 * The name "Enderdragon" was first made known through a tweet by Notch reading "raqreqentba," which could be decoded using the ROT13 cypher, translating to "enderdragon."
 * According to Notch on Reddit, there will only be one Enderdragon in the End.
 * The Enderdragon has its own separate mob folder containing separate designs; the old gray skin and the newer black skin.
 * Made of 61 cuboids, the polycount on the dragon is higher than all models in Minecraft. Notch joked about how Minecraft was "going next gen" when deadmau5 mentioned this.
 * Before it was textured, Notch reported how he was afraid to texture it as it was a complicated model. In the end, the dragon model was so complex Notch reported that he gave up making the texture manually and invented 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.
 * As of 1.9 Pre-release 5, Enderdragons:
 * No longer catch fire from lava or the fire aspect enchantment.
 * Can only be hurt below the 127 block map height limit. Getting Enderdragons to fly above the limit (in Creative Mode, Overworld) will prevent any damage that could be done to them.
 * Have their own achievement called "The End" which requires defeating an Enderdragon.
 * In terms of how difficult the Enderdragon will be to defeat, Notch tweeted that his design guideline for the dragon is "If I can beat it at all, it's too easy."
 * On October 12 2011, Notch uploaded a video showing why Enderdragons will not spawn in the main world, as they will destroy any block they come into contact with.
 * On Reddit, Notch explained why Enderdragons destroy matter.
 * When an Enderdragon destroys a block by means of flying through it, an explosion effect occurs and is identical to that of a TNT explosion.
 * When the player defeats the Enderdragon, leaves, the re-enters the End using another stronghold, all the endermen are gone.
 * When hit, it makes the same pain sounds as the player.
 * Enderdragons spawn on Peaceful.
 * This mob's attack is unique from others as it can send the player and mobs 'flying' back as opposed to other mobs' attack simply knocking the player back a little.
 * An enderdragon's attack can cause endermen to chase after it, should they survive the devastating attack.
 * It can be damaged by snowballs, because snow is made of water, and water damages ender-mobs. However, Snow Golems will not attack it.