- "He took a mermaid to wife and stole fire from the Storm God and carved the first ship from a demon tree that fed on human flesh."
- ―Euron Greyjoy
In the books
Ygg is a legendary demon tree who fed on human flesh. According to legend, the Grey King carved the first longship from Ygg's hard pale wood. It is unknown if Ygg was a weirwood, as the First Men of old hung the entrails of the condemned in the branches of heart trees.