Sona

Sona is an ancient shadowcasting technique for detecting unnatural vibrations and movement in the shadow. It is a way of "active listening" or "watching" the shadow -- typically used as a defense mechanism against magical attack. All shadowcasters are "aware" of the shadow, to varying degrees, but sona is a limited method of amplifying that awareness. Sona only detects changes that originate in the shadow itself -- echoes from the flesh are ignored. Notably, sona may be imbued into an artifact to create a sona tarr, thereby giving anyone (even a mundane) a limited awareness of change in the shadow -- basically, a limited signal that something magical is happening, but without much detail about what, exactly, that means. According to legend, sona was imbued into the walls of some towers, castles, or cities, to warn the ziraduun inside of impending magical attack.

Today, sona tarr are used by the Ardent during Trial to detect vibrations triggered by sh'thaen tarr when used on certain gifted individuals. Although the vast majority of people do not understand how this works, the tiny minority of educated shadowcasters, living in secret, view the Ardent's use of sona tarr as an abomination. This is because the signals from sona tarr may be easily misinterpreted (depending on the artifact) and may be caused by random, errant vibrations in the shadow, completely unrelated to the Trial. Moreover, the signals from sona tarr can be easily manipulated by a gifted shadowcaster -- enabling a malicious onlooker to affect the result of the Trial.

The dream equivalent of sona was originally called fidea, but this distinction has faded and sona may now refer to either the shadow or dream spell.