This is a 1.11 /summon command that summons a headless horseman!
Note: Minify the command to avoid issues :)
A bunch of awesome commands
A bunch of awesome commands part 14
TheMinecraftMan's Head
Cool Party Firework
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)