What is called?

In November 1979, Queen began what they called the 'Crazy Tour', playing nineteen gigs in the UK and one in Ireland. One of its central numbers consisted of Mercury walking in with an Ovation 12-string guitar to perform this piece; often the audience thought it was a joke as Freddie Mercury was not typically known to be a guitar player. However he could indeed play, and even if he was very modest about his guitar technique (he often introduced "Crazy Little Thing Called Love" by saying "I can only play three chords"), he played well.