A boss weaker then ED or WB.I'll edit this soon if it doesn't work.
Note: Minify the command to avoid issues :)
Cheat chestplate
Super cool potion!
A purple black checkered block just by one command
No one will get in your way
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)