Ihsahn (Vegard Sverre Tveitan) is a Norwegian guitarist, bassist, keyboard player, vocalist and lyricist. He is best known as the frontman of black-metal band 'Emperor.'
He was involved in several other projects including Thou Shalt Suffer and Peccatum, and now devotes himself to his solo project - 'Ihsahn.'

Literally everyone, ever. Including the writer of this definition.

God of Heavy Metal