Thor Rock Island

Thor Rock Island is an island that first appeared in the TV episode, "Appetite for Destruction" as well as the game, Dragons: Rise of Berk.

Dragons: Defenders of Berk
During the events of "Appetite for Destruction", the Dragon Riders survey dragon populations on several islands. As the Riders each mark dragons with different colored paint, they realize that dragons from one island are ending up on the others. They discover that these islands are being systematically destroyed and the dragon populations are migrating. Astrid and Hiccup travel to Boarhead Island which has vanished, then to Thor Rock Island and find it crumbling into the sea. A Screaming Death is responsible, destroying islands as it makes its way to Berk.

Other Appearances
Thor Rock Island does appear on the Interactive Map on the Dragons: Race To the Edge website. However, no description is given as with some of the other islands featured on this map.