Jan Axel Blomberg (born 2 August 1969) is a Norwegian drummer known professionally as Hellhammer. He is best known as the drummer of the black metal band Mayhem, which he joined in 1988, and is the only member to appear on all of their albums. In 1987 Blomberg, alongside Steinar Sverd Johnsen and Marius Vold, formed the avant-garde black metal band Arcturus (initially under the name Mortem), which broke up in April 2007 and reunited in 2011. He named himself after the Swiss extreme metal band Hellhammer. Praised as a talented musician, Blomberg is a three-time winner of the Spellemannprisen award. ()