Even before heavy metal was officially a Thing, the worlds of classical and guitar were crossing over. In December 1969, Deep Purple released Concerto for Group and Orchestra and in the decades since everyone from Metallica and Black Sabbath to Architects and Emperor has found ways to incorporate orchestral elements into metal, spawning the symphonic metal subgenre in the process.But what about in reverse? We asked Apocalyptica - the Finnish masters of reinventing metal songs in a classical style - to pick out ten compositions that are in dire need of a heavy metal makeover to help bring them ...