Make sure you read this. Name it JakeTheDog then tame it!
Note: Minify the command to avoid issues :)
Normal pokeball
Get my head
Troll your friends with this command!
Summon JakeTheDog!
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)