Astral Binding

This is a ritual known almost exclusively to the Githyanki and Githzerai, both denizens of the Astral plane. Astral energy and the Astral essence of individuals is a central part of Gith society and religion, and there are many rituals and traditions that occur in the daily life of the average Gith.
Astral binding is one of the less common rituals performed, and is only used in specific circumstances, when deemed appropriate by the Valorbound of the fortress. It involves the intertwining of the astral chords of the individuals involved, tying them in such a way that only the Wish spell can undo them. From then on, all the people whose chords were intertwined will be able to find each other on any plane of existence, regardless of distance. You may not know the exact location of the individual, but perhaps the next place you should go in order to find them, for example. The astral chord trails behind an individual.