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 purple black checkered block just by one command
A hacked sword
Garden furniture one command
A awesome minecart
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)