Mental Horror started its activities in 1993 as a traditional Death Metal band, following the leading bands in that time, in the beginning of 1995 they released their first demo tape, having great acceptance by the extreme Death Metal fans and making Mental Horror a known name in the underground scene.

Having line-up problems since the beginning, the band could only get stable in September 1997, with only one member remaining from the original line-up, Claudio C.

When Robles Dresch joined in as a drummer and Adriano Martini became the new guitarist, Mental Horror finally could play the purest, fastest and truest extreme Death Metal, ripping tunes of sheer musical atrocity and recording in February 1998 the first work with the new Mental Horror, the demo tape "Extreme Evolutive Trauma".

This demo tape was considered by many fans and the underground media as the most extreme demo that was ever recorded in Brazil, and this great events were followed by many gigs in Brazil with bands such as Krisiun. During this period, until June 1999, more then 1150 demo tapes have been distrubuted, achieving utmost respect in Brazil and through the world. Each day they got better and faster, and to prove that they entered the studio once again to record two more songs that helped them to achieve new opportunities, as the ones they already achieve with Extreme Evolutive Trauma, but the best opportunity found was the contract proposed by Necropolis / Deathvomit, and with them Mental Horror signed a contact expecting to unleashing a vicious record of pure death converted into music.