This command setting Ender Dragon spawner on your coordinates
Note: Minify the command to avoid issues :)
Give me the best Sword
Create scoreboard with players health
(/setblock) Ender Dragon mob spawner
Give me Elytra (21w11a)
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)