If you want know more about Herobrine seed, we will tell you a story about it:
In the internet, it is told, Herobrine is Notch’s dead brother, somehow embedded into Minecraft. But on the other hand, many people said that is not true because Notch has no brother.
Some people said it is an type of virus that manipulates game worlds, deletes threads and sends messages through the Minecraft Forums. Or that is an simply a figment of the user’s imagination and is certainly inspired by Slenderman.
But according to the community: The most popular theory among users is that Herobrine is a ghost or a demon and it has not canonically appeared in real life, and remained confined to technology.
There are many ways to spawn this creature, one way to summon him is a 3 by 3 square of gold blocks. On the ground, then with redstone torches in each corner and 2 netherrack on. Top of each other in the centre if this square. Light the top one on fire.