The Witherly Brother!
Note: Minify the command to avoid issues :)
Tried At The Furnace, Armor Stand Generation!
Steed 1: Royal Steed
Steed 4: Evil Steed!
THE NINJA STAR!
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)