The Skaal leader is an old Nord - Storn Crag-Strider. As a shaman and sage, he has gained knowledge of other dimensions and Miraak's plans. During the conversation (regardless of the chosen dialogue options) you will learn that your enemy is a Dragonborn as well. Long ago, he was imprisoned in the land Apocrypha and is now planning to return. The only way of returning to Solstheim is building enough temples dedicated to him. That's why some of the islanders became haunted by him and strange constructions are being built throughout the land. In order to destroy them (and therefore thwart his plans) you have to learn a new Shout, which is possible only in the Saering's Watch.