Kai Michael Hansen (born January 17 1963, in Hamburg, West Germany) is a heavy metal guitarist and vocalist.Hansen is the founder, lead guitarist, and vocalist of power metal band Gamma Ray. He is also the co-founder and former member of German metal band Helloween. He is a prominent figure in power metal and has sold millions of albums worldwide. He is regarded as "the godfather of power metal", having founded three seminal bands in the genre.