There are more than two bands under the name Rigor Mortis:

1- Originally formed in 1983 when schoolmates Harden Harrison and Casey Orr met Mike Scaccia. The three shared a love for horror/gore flicks and extremely heavy music, and that recipe helped them create a truly unique form of speed metal that had never been heard before. Within five years they had virtually created the thrash metal scene in Texas. In 1988, with Bruce Corbitt on vocals, Rigor Mortis released their self-titled debut album on Capitol Records, considered by many to be the first underground metal band to sign with a major label

They released their first album in 1988, titled Rigor Mortis. Rigor Mortis (the album) is competant, energetic thrash, punctuated by the blinding speed-picking of guitarist Mike Scaccia. The succeeding releases were the even more speed-metal album "Freaks" and the brutally hardcore-ish "Rigor Mortis Vs. The Earth". The band never seemed to rise above cult-level status, which possibly led to their breaking up.

In 1991 Mike left Rigor Mortis to become a full time member of Ministry, who he had been moonlighting with off and on since '89, and relocated to Chicago. Mike later returned to Dallas and formed League of Blind Women, a blues based rock band, which featured Rob Buck from 10,000 Maniacs.

In January 2003 the trio of Mike Scaccia, Casey Orr, and Harden Harrison reunited, with the eventual intent of possibly recording again. Now with original vocalist Bruce Corbitt on board as well, they are actively touring as of this writing, though their long-range plans are still unclear.

2-Pre-Immolation band of Bob Vigna and Tom Wilkinson formed in New York in 1986.

http://www.metal-archives.com/band.php?id=35975

http://www.myspace.com/rigormortisny

3-Turkish Gore/Death metal band found in İzmir.

4-German Speed Metal band that formed in 1982 and released one demo, First Assault, in 1985. Their song, "Tic Tac Toe," was featured on the Teutonic Invasion Pt. 2 Sampler released by Roadrunner Records in 1988

5-Goregrind band from Russia

6-Argentina Thrash Metal band formed in 1994
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