Horrified by Repulsion
The founding of grindcore is most often credited to Napalm Death, with their debut full-length Scum, released in 1987. Unfortunately, an equally good album (if not better) is often overlooked. Horrified by Repulsion, a band from Michigan, was recorded in 1986 but released in 1989. I find it to be more enjoyable than Scum because it's just so well put together. It's pure grindcore, which is a metal and punk hybrid and that is exactly what this album is.