Ender Dragons were powerful dragons that resided in a dark realm known as the End, populated by Ender Men.
The End consisted of multiple islands of End stone floating in space, separated by vast voids. Each island was presided over by a single Ender Dragon. The islands were dotted with multiple towers made from obsidian, each one topped with a magical crystal that could nourish the Dragon and heal it should it ever be injured. These towers were created by the Ender Men to prevent the dragon from devouring them.
Ender Dragons had a weak breath weapon; namely the ability to fire small bursts of hot flame from their mouths. However, they were powerful with magic. They could radiate an immensely powerful magical field that could, at short range, destroy almost any substance completely, leaving no trace and releasing no energy. Exceptions to this rule were End stone and some igneous rocks, the materials the End consisted of. The Dragons'bodies were made of End-material, meaning the dragons could pass straight through any block they couldn't damage. Ender Dragons ranged in size from 12 meters up to 100 meters in length. Much like the Ender-Men, their bodies contained hardly any biological components, making them negligibly senescent (biologically immortal). Ender Dragons very rarely bred, and only ever produced a single egg at a time. These eggs were of great value.
Ender Dragons had no sense of time, since they were biologically immortal. They would wonder the eerie realm of the End for millenia. Ender Dragons, although they had territories, made no lair since they never required rest or sleep. They were constantly in flight above their End-island. They also didn't hoard treasure.
Ender Dragons were incredibly aggressive and arrogant, but also very protective of the Ender-Men they ruled over, perceiving any intrusion into their territory, voluntary or otherwise, not only as a personal affront but a threat to their minions.
They preferred to fly high into the black skies of the End, were they would be almost invisible, and then ambush intruders. Ender Dragons were extremely hard to kill, since they could use their magic-field to destroy incoming projectiles. Also, the great obsidian towers could heal them once they took damage.
Behind the Scenes
The Ender Dragon is a boss from the game Minecraft. It resides in an eerie realm known as the End, populated by Endermen. The end is separate from the rest of the world, and can be accessed via a portal.
The Dragon is hard to kill. It had 100 hearts of health (10 times more than the player) and does 5 hearts of damage (it can kill an unprotected player in 2 hits). The Dragon is also constantly being healed by the crystals on the obsidian towers, and so these have to be destroyed before the dragon can be killed.
The Dragon can fly through any blocks in the game, and with the exception of obsidian, bedrock and end stone, deletes those blocks in the process.
The Ender dragon can launch purple fireballs in the X-Box 360 version of the game.