you can choose any mob you like!!!!
Note: Minify the command to avoid issues :)
EPIC BOSS SPAWNER
OP version:2
HEALTH BOOST 10 (not absorbation!!)
EPIC VILLAGER!!!
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)