It is a Zombie riding a Wither Skeleton Skull.
Have Fun!
Note: Minify the command to avoid issues :)
Potion of Defense (Resistance)
Cow Rider
Stone Soldier
Butter Ankles
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)
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