MY BEST FRIEND!
Note: Minify the command to avoid issues :)
Herobrine in one command ! (Don't spawn him!)
Red bull 2.0 (Aka Black red bull)
Angry Pigzombie (1.9.1)
More mobs in 1 command (Read The comments!)
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)