A wither skeleton with the head of a enderman.
Note: Minify the command to avoid issues :)
MINDBLOWER Chest
Wear TheDiamondMinecart's Head!!!!
Special Villiger
Lucky Potion (NO LUCKY BLOCK NEEDED =])
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)