I know very surface level stuff about the grindcore genre, but this is my absolute favorite, top number one, grindcore album that I listen to on repeat. Scum by Napalm Death released in 1987.
A split 7" between Japanese Doom Metal / Sludge group Corrupted, also with Italian grindcore group Cripple Bastards. Just pummeling and crushing stuff from Corrupted, who I think is just one of the heaviest sounding band there has been.