The Skirling

The Skirling is widely considered by the scholars of this world to be the source of all its magic, and I surprisingly happen to agree with them on this count. All 3 worlds I have visited have manifested their source in some kind of physical form, yet none are as dramatic as the Skirling, which assumes the form of a constantly raging storm.
When near this source, magic is noticeably stronger and more potent, leading it to be the subject of much investigation by Nalan's mages to develop its application. That being said the danger inherent of even being close to such power makes it difficult to study - the only way to reach the Skirling is by crossing the treacherous Mistwalk, since its strong winds render the sea far too rough for even the sturdy ships of the The Shattered Shores, and are only more impossible to brave through airship. 
Most people steer well clear of the Skirling, since erratic lightning strikes and strong winds make is considerable dangerous to be near - this goes double for the nearby waters.