This actually needs two command blocks.
Achtung: Minifiziere den Command um Probleme zu vermeiden :)
I am working on a map... in my realm.
NEW AND IMPROVED LITTLE PUFF!!! (Little Puff 2.0)
Check Out TheRedEngineer
Barriers!
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)