Mateo Guerrero made his comics debut in the mid-1990s. He broke through in the Spanish comic scene with the heroic fantasy series 'Crónicas de Mesene', of which two limited series appeared at Planeta-DeAgostini and Dude Comics between 1998 and 2000. He also did the juvenile series 'Cazadores en la Red' in the magazine ¡Dibus! en the juvenile supplement of the daily El País. Guerrero then left the Spanish market, and began drawing for the USA. After the unpublished 'Wildstorm' mini-series with scripts by Scott Lobdell, he joined Dreamwave Productions to become the penciller of the 'Warlands' title in 2002.
