Empty Space Beacons

The Lights use a compressed three dimensional space to travel between the solar systems in the galaxy. If they didn't, traveling across the galaxy would take millions of years instead of five months. When they first discovered the compressed space, they had no estimate how far they had traveled in it, hoping to be near the spot they wanted to be in normal space. many of them didn't like such an inefficient way of travel, so they devised a scheme to put mind beacons in the empty space at points near the various planets they inhabited. Using the beacons, they could easily travel from one planet to another, emerging in regular space near the spot they wanted to be.

The Dren also had an empty space they used for travel. It was much more compressed than the Lights, but any beacons they placed in it were always destroyed when they returned. They eventually encountered a creature that was so different from anything else in the universe they could not figure out what it made from. The creature attacked their minds, damaging them while causing great fear. Fortunately there were enough of them to scare off the creature allowing them to leave the space before any permanent damage was done. They discussed the idea of using modified beacon which could scare off the creatures, but decided not to since they existed in the space first, so it should be considered their home. When Eximius traveled through the space with Jack, they were followed by a few thousand of the creatures. She had enough time to examine a few of them at a distance and came to the conclusion they were not attacking minds, but trying to communicate. Since physics behaves differently in every three dimensional space, she believed whatever they were made from was destructive to mind matter. She deduced that they may have accidentally destroyed the beacons when trying to examine them.