Post-metal
Also called atmospheric sludge
Kind of Heavy metal
Mid-1990s–2000s heavy music that keeps sludge/doom weight and writes long, dynamic, often instrumental-adjacent forms (Neurosis, Isis). It is a style of Heavy metal. Sludge metal supplies the slow ugly riff; Crust punk supplies the Neurosis squat-hall hinge. Post-rock leftover as a neighboring dynamics name, not a parent. Doom leftover as already sitting on sludge. Empty Given after that check is historical: blackgaze is a sibling meeting, not a child.