The Rains Of Castamere by The National (from Game Of Thrones Season 2 Episode 9 end credits)
Swear to god, when this started playing at the end of the episode, it felt like my house was suddenly located somewhere in Antarctica. Such goosebumps.
Honestly, nearly everything about this show gives me goosebumps (though much of the credit should also go to George R.R. Martin for the books it’s based on), but yeah, the music is a huge part of it for sure. Another of my favourites is the music at the very end of the last episode of season 1, when (SPOILERS FOR ANYONE WHO HASN’T SEEN IT/READ IT) Daenerys rises from the ashes of Drogo’s funeral pyre with her dragons. So epic. :D