The Storm Tongue

An ancient language said to have been spoken by the priests of the Word of the Storm religion, the Storm Tongue was said to sound like an actual storm when spoken by eloquent priests. When engraved into stone and wood, the words would feel like a storm written down in symbols, as if they did not actually write but simply communicated the feel.
In fact, some suggest that the Storm Tongue was nothing but gibberish. On the other hand, there are those believing the priests knew some form of sacred language, and that the religion disappeared after they discovered too much. The various artefacts that the Gray Sails has documented, appear to use similar symbols, which gives credibility to the theory that the language was a real thing.
Because the Storm Tongue was only spoken by priests, and only during special ceremonies, no trace of the verbal language remains, and only damaged and partial engraved texts of the written word. Unfortunately, there is nobody that can read these, which means that there is no known way to validate whether the texts hold any actual secrets regarding Storms, or just useless administrative texts.
It should be noted that recent research by the Gray Sails suggests that perhaps the Stormlanders are descendants that may or may not partially speak the language. Some suggest to undergo an expedition to the Storm Lands, to ask for aid translating all the texts in the archive. However, some members prefer waiting until an artefact is discovered which is more readable. Rather than give away hints too early, they deem it better to make absolutely sure the Gray Sails have texts worth translating, before exposing that perhaps people remain that may actually be able to translate the texts.