MX is a Brazilian thrash metal band, formed in the early 1980s in São Paulo. Its name comes from the American ICBM MX missile. MX was one of the most important bands from the Brazilian thrash metal scene during the late 1980s. The band’s sound is closer to the Bay Area thrash scene than the Brazilian scene, although many of the vocals were death metal grunts. However, some of its later work was fitting as post thrash.

MZ was the opening act in Brazil for Testament in 1989 and Exodus in 1997.
The band released two studio albums during its heyday, Simoniacal in 1988 and Mental Slavery in 1990, on the defunct label Fucker.
Shortly after the release of Mental Slavery, the band split up, but reformed in 1997, releasing the EP Again in that year and the album Last File in 1999. The band split up again shortly after.
The band reformed for a second time in 2005, planning to tour and to release a new studio album. The first two albums have been re-released under the Marquee Records label.

(http://en.wikipedia.org/wiki/MX_(band))

MEMBERS – CURRENT LINE-UP

Alexandre Prado Favoretto “Morto” – vocals, guitars
Décio Frignani – guitars
Alexandre da Cunha – drums, vocals
Alexandre Gonsalves “Dumbo” – bass guitar

DISCOGRAPHY:
•    Simoniacal
•    Mental Slavery
•    Last File
•    Again

Here is the list of 10 best riffs of MX: