A boss weaker then ED or WB.I'll edit this soon if it doesn't work.
Note: Minify the command to avoid issues :)
A lab by one command
Hoverboard
Space Walkers in 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)