It would have to be Slayer, since they were around before Sepultura and influenced them. Also, Slayer is talked about more by the general public, so they're probably slightly more well known in the world of music than Sepultura is.
Probably Pantera, especially since all the fringe kiddies jumped aboard that bandwagon in 2004. Unlike some bands, departing from playing true Metal didn't bolster Sepultura's popularity.
Megadeth all the way
SLAYER!!! Anthrax has sold around 10 mil records while Slayer has sold from 15-35 mil records
Megadeth
Metallica ,Megadeth,Slayer,Anthrax
Metallica, Megadeth, Slayer, Anthrax
It is difficult to single out any one Megadeth song as the number one song by Megadeth because the band was so popular. However, Holy Wars: The Punishment Due was one of Megadeth's most popular songs, so it could be argued that it is the number one song by Megadeth.
SLAYER!!! Anthrax has sold around 10 mil records while Slayer has sold from 15-35 mil records
Megadeth
Aerosmith is more popular than Megadeth, because they get played on the radio a lot more than Megadeth and sold more records as well.
Slayer, Anthrax, Metallica, and Megadeth
Both bands are very popular, but ACDC reached the masses more than Megadeth so ACDC wins this one.
Metallica ,Megadeth,Slayer,Anthrax
Green Day
Metallica, Slayer, Motorhead, Black Sabbath. Metallica and Megadeth.
Bands such as Megadeth, Slayer, and Metallica were a MAJOR influence on them!!
Metallica, Megadeth, Slayer, Anthrax
Metallica
It is difficult to single out any one Megadeth song as the number one song by Megadeth because the band was so popular. However, Holy Wars: The Punishment Due was one of Megadeth's most popular songs, so it could be argued that it is the number one song by Megadeth.