Herobrine

Herobrine is a creepy ghost-like entity who likes to terrorize Nowhere Men and anyone who asssociates themselves with them. He has a menacing appearance and attacks people on sight, but also constructs strange monuments that worship himself.

He can fly, teleport and summon objects at will. He is beleived to be the ghost of a man who was cast into the Nether and never returned. Herobrine supposedly sleeps in the Nether so this theory is plausible. He also apparently commands a legion of the dead, which is less plausible.

Information Guy has supposedly seen him, since Information Guy knows everything about everything about Nowhere.