Wavetamer

Wavetamers are professional guides who serve aboard ships to ensure safe passage through the various seas of Mundus. Often they are priests of Gwilha, as they are chiefly responsible for making sure that the sailors and their passengers pay proper respect and do not offend the Tidebringer with their behaviour in her realm.
However, their responsibilites do not end at keeping Gwilha happy. There are other dangers to avoid upon the seas, such as treacherous shallows, territorial sea creatures, monster-infested shorelines and islands occupied by pirates. Knowledge of such risks and how to avoid them fall under the responsibility of wavetamers as well.
They are part holy guide, part navigator, and part manager. The last of these is arguably the most challenging task aboard a ship, as sailors can be notoriously hard-headed, unlikely to pay heed to the warnings of someone not from their own crew. A successful wavetamer knows how to keep discipline board a ship, even if it means occasionally stepping on the toes of the captain itself.
Wavetamers are a common sight on great trade vessels, as rich merchants know better than to risk losing their cargo at the whims of divinity. Passenger barges, fishing boats, pirate ships and other vehicles manned by less prosperous people can rarely afford the services of a wavetamer, as their service is a precious one. The Sailor's Mistress has expensive tastes when it comes to sacrifice, and wavetamers are well aware of the value of their expertise.
It is said that the legendary hero who lead the humans away from the lost continent was the first of the wavetamers. This messianic figure saved mankind from the hungering waves, and the tradition of wavetamers is well alive and respected in various human realms to this day.