"Richard and I are really big fans of the show and we knew a couple of other musicians that had also become extras. We just asked! It was the third episode of the last series where they had the massive battle.
"At the time it was the most expensive single piece of television ever filmed, so even if you don't watch the programme, just seeing enterprise on that level and walking into a room full of extras, 300 men with beards on was really funny," she said.
And the "Murder on the dancefloor" hitmaker added that the moment was so surreal, that it was "slightly absurd".
She added 'It was definitely fun, there was a lot of giggles as it was slightly absurd. It was a very dark battle so we couldn't see ourselves at all. But we were there in spirit."
The eighth and final season of "Game Of Thrones" aired earlier this year, bring to an end the much-loved fantasy drama series.