From Path of the Vampire Wiki
What is Vathiá?
The Vathiá is one of the 3 spiritual realms known to vampires. The other two are the realm of shadows and the mortal afterlife, though little is known of the latter, and there are thought to be more spiritual realms in existence.
Also known as the mindscape, or the collective unconscious, it is a reality comprised of pure thought, both the individual and the collective. Indeed, it is speculated that the Vathiá was created when the first thought was formed, and each new thought that each living creature had added to the Vathiá, extending it and giving it form. The realm even retains faint echoes of dead memories and thoughts, which never seem to fade from the Vathiá, but drift through it eternally, as each new life simply adds to the infinite expanse.
However, it is not thought alone that lives in the Vathiá; it is radio waves and electronic signals and wireless data in all forms. Somehow, in modern times, radio waves and wireless data has interrupted the collective thought cloud which makes up Vathiá. As such, the realm now includes -- not just thought -- but all kinds of information in all forms, from binary data to voices broadcast on radio waves.
This change in the makeup of the Vathiá realm has been blamed for the cause of many modern changes, including the dying-out of the fae.
Although a Telepath whose mind has been drawn into the realm of pure thought would be at risk (their minds can be harmed if something happens to them in the Vathiá), it is thought to be the thing that gives Telepaths their ability of Technokensis, among other things.
Entering The Vathiá
Only Telepathic creatures can enter the Vathiá.
While it is possible for vampires to learn gifts that utilize the collective data-stream of the Vathiá (such as technokenisis), only a telepathic-path vampire can actually enter the Vathiá itself, via a deep meditative state brought about by what was known as the Vathián Meditation power (a mastery power available only for telepaths).
Telepaths without such a gift are still able to view the Vathia in its most basic form, and even manipulative certain thoughts and signals, but they cannot enter the realm in the same way a Vathián meditator can. Regular vampires not of the telepathic path can manipulate, but not view / enter the Vathiá, no matter what powers they gain. Non-telepaths can, however, be drawn into Vathiá by those willing to take them.
As the Vathiá is a non-physical realm, one does not see it with their eyes. Instead, the person's mind will view it as a stream of subconscious thought and electronic signal, where neither the individual, nor those they encounter in the Vathiá have any recognisable humanoid form. However, as the mind is ultimately responsible for all physical senses, a telepath concentrating in the Vathiá is able to translate streams of thought or data from patterns of dancing light and shapes into sounds, text, images from random memories, or even scents.
Please note that if you are roleplaying your character reading flashes of memory in the Vathiá or intercepting electronic signals, you may not roleplay the discovery of any specific memory or electronic signal, as exploring the Vathiá is completely random and there is no discernable pattern to the ways it stores data, so you cannot realistically accidentally stumble across information about a particular person. Of course, this does not change the usage of other telepathic powers with specific descriptions to the contrary (for example, hacking using technokinesis).
Before the invention of radio, wireless devices, and the containment of electricity, the Vathiá was a peaceful realm of pure thought belonging to all living creatures. Telepaths would stay there for days on end, exploring images and words and experiences, or simply watching the flow of the Vathiá as it passed by, which was extraordinarily beautiful.
The vision of beholding the Vathiá could best be described as spirograph of restful colors and shifting geometric shapes, all intertwining and snaking as far as the eye could see. It is a vision often described by those high on mind-altering drugs, or those close to death; and indeed, it is possible that those individuals are the only ones besides telepaths who were ever fortunate enough to experience the purest Vathiá, before it was corrupted by human invention.
To say the Vathiá has changed since the invention of radio would be accurate. To say likewise about the time since the invention and popularization of wireless computer signals would be an understatement.
Where once was restful colours is now a vibrant mix of all shades, from the darkest black to the most violent yellows. Moreover, the shapes themselves are now intermixed with solid, static, mathematically perfect geometric shapes. All the while the realm flickers as though thought was being interrupted by static.
Perhaps most worrying of all is the fact that there are far fewer "dead memories" and thoughts than there once were, which has lead some to believe that the consciousness of the dead is being snuffed out or corrupted by artificial signals.
Although the Vathiá is still a beautiful place, it is far less restful than it once was.
Dangers in the Vathiá
The modern-day Vathiá poses dangers to telepaths, as it is possible for their minds to be damaged by various things. It is thought that the electronic signals caught in the Vathiá are responsible for these potentially harmful disruptions, but the fact is nobody knows for sure.
Lost in Dreams
It is possible for telepaths in the Vathiá to become lost and unable to find their way out. Once, a telepath could simply return to an alert state in the physical world at will. Now, however, inexplicably, some telepaths find themselves unable to return to consciousness. They have described the feeling as being trapped in a dream, knowing it's a dream, but being unable to wake yourself.
Overwhelmed by Information
Some telepaths, when attempting to read random electronic signals such as binary fragments, can become overwhelmed by information. This can cause serious damage to a telepaths mind, and though a vampire's mind heals in time, it is still exceedingly painful when this happens.
Fae in The Vathiá
There have been some rumours of fae who reside, or at least visit the Vathiá. This is said to have always been the case, but either way, fae in the Vathiá are said to be able to harm a vampire's mind quite badly, and force them out of the realm of collective consciousness.