Lord Dour is a song written by Beren Merryweather which earned him the animosity of the Valemen accompanying him. The song is about how Nathaniel Arryn became Lord regent for his brother's son Theon Arryn.
Let me tell you the story of a Falcon most wise
He ruled o’er the vale to the day that he died
None would have guessed how soon he would fall
Nor that it'd be at the tourney of old Harrenhal
The weapon of women the Titan did pick
He poisoned the Warden, left the Vale to his chick!
So they called in the cruel brother, the Falcon most grim,
The justice, the cold one, to rule then for him!”
“He did so with iron, with bronze and with steel
All without honor, his wrath they would feel
The bird never smiled down from his nest of power,
So they named him the Stone Man, Lord Falcon the Dour!