Yeah. It's a cave spider dressed in a diamond block.
Note: Minify the command to avoid issues :)
Unlucky Potion (NO LUCKY BLOCK NEEDED =])
Special Villiger
WEAR MY HEAD!!!
Survival super kit
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)