On Fire is the fourth album of the Italian heavy metal band Mastercastle.

27, known as the Moonlight Sonata, written by Ludwig van Beethoven The album was recorded starting from March 2012 and was finished in December 2012.

"Once again all lyrics were composed by Giorgia Gueglio, "I started the lyrics with the intention of writing a concept album with the title "Metals", concerning metals in metallurgy, chemistry, alchemy and magic.

But during their creation I found my lyrics full of sentiments, suffering and emotions.

Many tracks have a title with a metal within, but these are "warmed" by blood, my/our human warmth, the passion of making music in a difficult world.