Terje Kretz was the artist of several comic series of the 1980s. In 1982, he created 'Dido og Trollmennenes Kamp'. Two years later, he came up with his most famous creation, the viking strip 'Ravn'. The texts were by Harald Hårfagre, with whom Kretz also cooperated on the adventure series 'Trollsvans' from 1986.