Spanish heavy metal foursome Obus was formed in Madrid in 1980 by guitarist Francisco Laguna and bassist Juan Luis Serrano, who were soon joined by drummer Manolo Cano (who was later replaced by Fernando Sanchez). After Fortu Sanchez became the band's leading vocalist, Obus signed up to local independent label Chapa Discos, recording Preparate, produced by Luis Soler and Tino Casal. The band debuted live on November 6, 1981. They issued Poderoso Como el Trueno in 1982 and El Que Mas in 1984, featuring "Alguien," composed by Iron Maiden's Adrian Smith. After touring South America for the first time, Obus recorded 1985's Pega Con Fuerza, featuring the hit "Te Visitara La Muerte."