Ordo Obsidium

Funeral Doom Metal

2 Albums

Ordrhein

Black Metal

2 Albums

Oreamnos

Black Metal

3 Albums

Orelisk

Black Metal

1 Album

Organ Dealer

Grindcore

3 Albums

Organ Trail

Death Metal

3 Albums

Orgone

Avant-Garde Metal

4 Albums

Orgy of Carrion

Black Metal

7 Albums

Orialus

Metalcore

1 Album

Origin

Technical Death Metal

10 Albums

Original God

Metal

9 Albums

(Origin Unknown)

Metalcore

1 Album

Orinoco

Metalcore

3 Albums

Orm

Doom Metal

2 Albums

Orodruin

Doom Metal

3 Albums

Oromet

Funeral Doom Metal

2 Albums

Orphans of Doom

Metal

2 Albums

Orthodox

Metal

5 Albums

Oryad

Symphonic Metal

2 Albums

Oryon Rex

Nu Metal

1 Album

ORYX

Sludge Metal

7 Albums

Osculum Serpentis

Black Metal

7 Albums

OSI

Progressive Metal

5 Albums

Osi and the Jupiter

Folk Metal

11 Albums