From A Wiki of Ice and Fire
Red Rain is a Valyrian steel sword belonging to House Drumm.
The sword came into the possession of House Drumm when Hilmar Drumm took the blade from an armored knight[N 1] with nothing but his wits and a wooden cudgel. From then on he was called "Hilmar the Cunning".
A Feast for Crows
Lord Dunstan Drumm draws and displays Red Rain during the kingsmoot.
- ↑ Fans have theorized the knight to be from House Reyne whose coat of arms depicts a red lion.
- ↑ 1.0 1.1 A Feast for Crows, Chapter 19, The Drowned Man.