30 Seconds To Mars style in music has changed alot since the
band was formed. The self-titled first album by 30 Seconds To Mars
was definitely verging on heavy rock. The second album A Beautiful
Lie got a bit softer but was still classed as rock.
Their third album This Is War uses less of the heavy guitar
strumming and more of the vocals. The track This Is War was the
heaviest on the album.
Right now 30 Seconds To Mars could be classed as rock/pop.