The moons

There are three moons orbiting the planet, one large and two small.

The large moon, Erea, is also the closest moon, and it's pull controls the tides. It is large enough, and close enough to the planet to totally eclipse the sun when it travels across it, and it moves at approximately the same speed as our moon, so there will be around four weeks between full moons. 

The two small moons are further away, and their gravity pull isn't strong enough to have much effect on the tides. The closest of the two, Cana, crosses the sky at approximately half the speed of Erea, and thus it is every eight weeks. It is too small to eclipse the sun, but those brave enough to stare at the sun as it passes might make it out as a dark spot traveling across the sun. The one furthest away, Xi'n, creeps across the sky, being full every half year. It is too small to spot as it travels across the sun. 

Allignment. There are times when all the moons are full, and on a line from the planet. Those nights are special, as magic is more powerful, and the tides are more severe.

Type

Natural