Setelin Campaign Primer

Welcome to the world of Setelin. A medieval high fantasy world.
615 years ago an astral storm passed through the planes causing massive destruction to them. The storm was powerful enough to shift planes and power between gods, new ones appeared and some even vanished. It even affected the primary plane moving planets and sending surges and gaps of magic throughout the worlds.
Erta is a planet with 13 orbiting moons, the 14th one crashed into a sibling during the astral storm
It is a large world with a significant amount of water covering it. There are three large continents, a few smaller ones and a significant amount of variably sized islands. The constant orbiting of the moons causes tides to submerge some lower lying islands.
Many ships travel the world for trade and exploration, and some with more malevolent goals. Few airships travel as well, kept aloft by a rare stone that owners and miners all to gladly keep a secret, all to ensure that airships stay the property of the wealthy and powerful.
The coastal city of Pria is where we start our campaign the capital city of the country of Luram. Dirty white walls with blue waves near the top of them layered from several expansions the city made of the 600 years it has existed. 
From a distance the moonlight tower is visible to the north beaches of the city and its beacon, a bright blue magical light resembling a full moon. The Arcanum Magani, a scholarly group studying magic houses its home in a tall building sticking out of the skyline of the city.
A good 50 ships are docked at the port from all across and caravans enter and leave the city constantly.