Just Use This To Summon Herobrine.
Note: Minify the command to avoid issues :)
Mobs In A Book -- WORK IN PROGRESS
OMG FLYING SQUID
MOST OP SWORD!!!
Frozen Ender Dragon!
Pet ENDER DRAGON!!!!!
Wither Storm Boss in ONE COMMAND
HEROBRINE COMMAND
HEROBRINE BOSS BATTLE (See YouTube for details)