d
Note: Minify the command to avoid issues :)
Notch Boss Battle (Almost Impossible to kill ALMOST not impossible)
More Mobs: Frozen Zombies in 1 command. 1.8.7 (Read The comments)
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Armor Stand killing someone!
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)