You can only summon this IN THE NETHER!
Note: Minify the command to avoid issues :)
skeleton max
Traveler
Nether Chicken
HYDROGEN CYANIDE
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)
amazingsimon
amazingsimon
darkknight3227
galbby5
deadpoolbadhair