Ego

The Ego is an invisible membrane that covers a Human's body and holds together their consciousness. Unlike the Id, Ego's can not interact with one another or the world in any way, and must remain entirely solid in order to function. Without an Ego a human will dissipate into their consciousness and receive [Enlightenment]. This acts forces upon a serious amount of trauma onto the consciousness, effectively killing and corrupting it. Because of this, Ego's do not have different physical forms like Id's are capable of. Instead Egos all take the form of a ghostly apparition.

Due to the solid form of the Ego, it's defenses are several times more powerful than the Id and able to resist much more damage. This of course comes with the drawback of their being no way to for an Ego to reform. Chaining and Linking are not entirely out of the question, however they are both extremely dangerous practices that would likely require some sort of mediator or special environment to resist the temptation of Enlightenment.

Ego's are entirely unique to Humans, and were created specifically by the Idcarnation as a means of separating humans on a spiritual level. Her theory was, without any kind of means of spiritual connection, Humans would be forced to live in a world where they were all alone and without any kind of 'real' connection.