Atuna's Cypher

Atuna's Cypher is a purportedly unbreakable encryption cypher used for secure communications throughout Telarul. It is called Atuna's Cypher because it was created, and continues to function, with the help of the godess Atuna. Atuna's Cyper works on written language only.

Encryption and Functionality

A message or document written in any language can be encrypted with the cypher through a special ritual. Only clerics of Atuna, and some select others, have the necessary divine connection to preform said ritual.
The ritual requires an original text written in a language that is understood by the caster, along with several quite expensive material components. The actual components needed are unknown to the larger public, but it is widely understood to cost the equivalent of about 4 gold per 10 words. During the ritual, the caster can specify who will be able to read the encrypted text. This can be individual people, in which case the caster needs to know the name of the person in question, or boarder groups. Specifying groups of people is usually avoided, as the specification is bound to include someone who's loyalties are questionable. For example: specifying the closest ministers of the Opal emperor also includes any ministers who are less scrupulous, or even outright spies.
To anyone not specified in the ritual, the cyphered text appears to shift and morph on the page, comprehension always seeming just out of reach. When the intended recipient lays eyes on the document, the text will shift into a language understandable to the reader. To preserve as much nuance as possible, the cypher will select the language which can best convey the meaning, prefering the original language if possible. If there is a concept that does not propperly translate, the cypher will add a footnote to inform the reader of this discrepancy, along with an attempt at explaining the original intricacies. Only the intended recipients will see the legible text, anyone looking over their shoulders will still see the shifting letters.

Usage

Due to the small amount of people with the knowledge, as well as the cost associated with encrypting texts, usage is limited to the wealthy or those in power. The cypher is mainly used in diplomatic communication between the nations of the world, as well as in the creation of documents for secret societies.
The built-in translation and mistranslation-prevention mechanisms make cyphering a text helpfull beyond secrecy. Some diplomats prefer to send a cyphered text even if the contents are public knowlede, if they know the recipients do not speak their language natively.

Creation

On the 26th of Ysa 3430 Emperor Nándor the Third commissioned his clerics of Atuna to create a secret cypher for use in official communications. After communing with their god for three months, the clerics returned with the knowledge of Atuna's Cypher

Attempted Circumvention

Most empires and kingdoms, as well as most major underground organizations, have ongoing investigations into breaking the cypher. This with the intention of intercepting and reading cyphered messages for diplomatic or monetary gain. These endeavors are severely hampered by the divine nature of the encryption.
It is unknown if some organization has already succeeded in breaking Atuna's Cypher, because if someone had, they would be keeping it a secret. Clerics of Atuna beleive that their god will notify them when such a breach happens.