O

Ossuary

Oppressor

Oranssi Pazuzu

Omega Infinity

October File

Obscure NWOBHM Releases

Overdrive

Omnium Gatherum

Orden Ogan

Odd Dimension

Obsession

Olympos Mons

Old Forest

Orcrypt

Organic Infest

OZ

Opera IX

Once Human

Osmose Productions

Oceans

Oak

Odious Mortem

Ominous Ruin

Ominous Scriptures

Onlap

Obsequiae

Outergods

Ondskapt

Obscura

Old Man’s Child

Opeth

Origin

Otep

Overkill

Ozzy Osbourne

Of Mice And Men

Orange Goblin

The Ocean

Omnihility

Ovids Withering

Obituary

Onslaught

The Ominous Circle

Obsessed, The

Oceans Of Slumber

Orphaned Land

Orchid

Ominous Circle, The

Orkan

Orpheus Omega

Overtorture

Obscenity

Order Of Chaos, The