Acid Bath

Acid Bath is an influential Sludge Metal band from Louisiana, formed in 1991. Their unique musical style combined sludge with elements of Black Metal, Death Metal, southern rock and blues-rock. While they are pretty much unknown in the mainstream, they have a significant underground fanbase and are considered a cult band by many.

In 1997, bassist Audie Pitre was killed in a road accident by a drunk driver. The band disbanded soon afterwards, having released just two studio albums during their short lifespan. Despite the short career, they are considered one of the major bands of the subgenre, alongside more long-lived bands like Eyehategod and Crowbar.

Former members:

Dax Riggs - lead vocals
Sammy "Pierre" Duet - guitar, backing vocals
Mike Sanchez - guitar, backing vocals
Audie Pitre - bass guitar, backing vocals
Joseph Fontenot - bass guitar
Jimmy Kyle - drums
Tommy Viator - keyboards

Discography:

When the Kite String Pops, 1994
Paegan Terrorism Tactics, 1996

Acid Bath provides examples of the following tropes:

Contemptible Cover - The artwork they used for their albums was done by several infamous serial killers such as John Wayne Gacy, Richard Ramirez, and Kenneth Bianchi. Also, the cover for Paegan Terrorism Tactics features a rather macabre painting by euthanasia activist, Dr. Jack Kevorkian.
Darker and Edgier: The demos are more harsh and abrasive than the "studio" versions of the songs.
Drugs Are Bad: It's been confirmed by multiple members that the band broke up not because of Audie's death, but because of severe heroin usage and abuse by virtually everyone in the band.
Lyrical Dissonance: The songs "Scream of the Butterfly" and "Bones of Baby Dolls" are smooth, acoustic songs with rather horrifying lyrics.
Mohs Scale of Rock and Metal Hardness - Their gentler songs range from 2-5. Their harsher songs span the range from 6 to 10.
Neoclassical Punk Zydeco Rockabilly: The best way to describe them is the bastard child from an orgy between a blues band, a death metal band, and a sludge band - with some other genres thrown in every now and then.
Sludge Metal
Soprano and Gravel: A rare non metalcore example from one man.
Subverted Rhyme Every Occasion - Partial example from "Paegan Love Song":

You scream,
I scream,
Everybody scream
For morphine

Surprisingly Gentle Song - "Scream of the Butterfly", "Bones of Baby Dolls", "New Death Sensation", and compared to some of their more abrasive material "Graveflower".
Title Drop: In the song "Bones of Baby Dolls" for When the Kite String Pops.