I used MrGarretto's command combiner, so this is not entirely mine.
Note: Minify the command to avoid issues :)
Unstable Potion
Herobrine /summon
Batman Cape and Cowl
Disguised Boots
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)