System of a Down's Serj Tankian made a surprise appearance at a recent Game of Thrones: A Live Concert Experience performance in Los Angeles to sing the series' "The Rains of Castamere."
The singer lent his unique vocals to the resounding rendition of the track, which was
This article originally appeared on www.rollingstone.com: See Serj Tankian Perform With ‘Game of Thrones’ Concert in Los Angeles