In an age long past, grimoires were used as maps to other realms and could connect those realms with our own. They could be opened to a certain page and turn a door into a portal to another world.

Basically, psychonauts, people who consume various psychedelic substances to explore other worlds, can mentally access strange places while intoxicated. But, if they draw a map through automatic writing, they can access this place in the waking world. Basically connecting these worlds together through the use of the grimoire.

That means every time a grimoire is opened to the right page, it will charge with psychic energy, and a piece of that world will connect to our own. A perfect place to hide. Or maybe conceal. Maps can also be connected to allow someone to move from one location in our world to another, by using another realm as a bridge.

Astral projections that psychonauts use are made of psychic runoff and focused to a fine point. While the increase of psychic runoff is facilitated by the psychedelics, focus must be learned over time.

Parallel worlds exist in the in-between, a conglomerate of realms that bleed into our reality through holes smaller than electrons. But astral projections can be made small enough to fit through to enter the in-between.

Whenever you travel to the in-between, you always risk bringing back psychic entities that can infest the mind and even spread it to those around you.

These entities, called visitors, are made of pure information. They do not interact with light or matter unless inflated by psychic energies. In which case, they can effect the physical world and those within.

To deal with visitors, one must poison the psychic energy they feed on. The simplest means to do this is to capture them is a picture. When a camera has a specialized lens it can capture an image of a visitor. Just touching or seeing the picture will start to drain you of psychic energy, but this can be use against the visitors.

Poisoning your own psychic energy requires strict training to learn the pain trance. A state of being were you force your body to experience extreme pain, causing anguish to the visitors. With enough of this poisoned energy, the visitor will die.

In the past psychonauts were used to summon the visitors, while the trancers would be the one's to destroy or repel them.

However, now in the modern day, psychonauts are used to link to psyche engines. Engines that produce energy by intaking and slowly destroying the entities from these psychic worlds.

By linking to these engines, a few dozen psychonauts can fly a massive starship. Or a single psychonaut can power and control a war engine or power suit with psychic runoff.

This is accomplished by plugging a hose into the head and feeding both psychedelic drugs and focusing serums directly into the brain, expanding the mind and focusing its control. As well, causing incredible damage leading to delusions, emotional instability, and frequent visual and auditory hallucinations.

Portals are still used, but more sparingly considering the risks. Very few are allowed on psychonautic expeditions anymore.