Obereg (RUS)

Heavy Metal - Russia

Oblachnyj Kraj

Heavy Metal - Russia

Oblivion (FRA-2)

Heavy Metal - France

Oblivion AD

Heavy Metal - USA

Oblivion Sacrifice

Heavy Metal - USA

Obsession (ARG)

Heavy Metal - Argentina

Obsession (USA)

Heavy Metal - USA

Obsidian (BEL)

Heavy Metal - Belgium

Obsin

Heavy Metal - Brazil

Obstinato

Heavy Metal - Chile

Obstruction

Heavy Metal - Hungary

Obstsalat

Heavy Metal - Germany

Obús

Heavy Metal - Spain

Occasion

Heavy Metal - Netherlands

Occitania

Heavy Metal - Spain

OCD

Heavy Metal - France

Oceanhoarse

Heavy Metal - Finland

Oconnor

Heavy Metal - Argentina

Ocreata

Heavy Metal - Mexico

Octo Hora

Heavy Metal - Germany

October 31

Heavy Metal - USA

Odax

Heavy Metal - USA

Oddiss

Heavy Metal - Russia

Odica

Heavy Metal - Ecuador

Odin (USA)

Heavy Metal - USA

Odisea (ARG)

Heavy Metal - Argentina

Odisséia

Heavy Metal - Brazil

Odium (USA)

Heavy Metal - USA

Odyssey (RSA)

Heavy Metal - South-Africa

Offroad

Heavy Metal - France

Ojos Negros

Heavy Metal - Argentina

Oker

Heavy Metal - Spain

Olan

Heavy Metal - Malaysia

Old Amoon-Há

Heavy Metal - Brazil

Old Mother Hell

Heavy Metal - Germany

Old Serpent

Heavy Metal - Greece

Old Wolf

Heavy Metal - USA

Old Yron

Heavy Metal - Italy

Oldenwood

Heavy Metal - Bulgaria

Older Jack

Heavy Metal - Brazil

Oliver Dawson Saxon

Heavy Metal - United-Kingdom

Oliver Weers

Heavy Metal - Denmark

Olvy

Heavy Metal - Russia

Olymp

Heavy Metal - Germany

Olÿphant

Heavy Metal - USA

Omas Kojas

Heavy Metal - Estonia

Omega Reign

Heavy Metal - USA

Omega Ryde

Heavy Metal - USA

Omen (USA-1)

Heavy Metal - USA

Omery Rising

Heavy Metal - USA

Omitah

Heavy Metal - Brazil

Omnia Transit

Heavy Metal - Spain

Omnislash

Heavy Metal - USA

One (FRA)

Heavy Metal - France

One Hell Of A Christmas

Heavy Metal - Denmark

One Last Legacy

Heavy Metal - Germany

One More Page

Heavy Metal - Turkey

Onirico

Heavy Metal - Colombia

Onirion

Heavy Metal - Spain

Only Sons

Heavy Metal - Poland

Onmyou-Za

Heavy Metal - Japan

Onyx

Heavy Metal - Sweden

Open Fire (PL)

Heavy Metal - Poland

Open Mind

Heavy Metal - Argentina

Oracle (USA-1)

Heavy Metal - USA

Oráculo (BRA-1)

Heavy Metal - Brazil

Oráculo De Delfos

Heavy Metal - Brazil

Oral (UK)

Heavy Metal - United-Kingdom

Oratoria (RUS)

Heavy Metal - Russia

Orchidea

Heavy Metal - Czechia

Ordalía (BOL)

Heavy Metal - Bolivia

Orfos

Heavy Metal - Spain

Organ Donor

Heavy Metal - USA

Orgus

Heavy Metal - Peru

Orion (ESP)

Heavy Metal - Spain

Orion (NL)

Heavy Metal - Netherlands

Orion (VEN)

Heavy Metal - Venezuela

Orion's Reign

Heavy Metal - Greece

Orizzon

Heavy Metal - Brazil

Orlan

Heavy Metal - Russia

Oro (ESP)

Heavy Metal - Spain

Orphan Allies

Heavy Metal - USA

Orpheus (NOR)

Heavy Metal - Norway

Orquídea Negra

Heavy Metal - Brazil

Osairis

Heavy Metal - Singapore

Oscura Cepa

Heavy Metal - Argentina

Oscura Tentación

Heavy Metal - Spain

Osiris (CAN)

Heavy Metal - Canada

Osmi Putnik

Heavy Metal - Croatia

Osmium Guillotine

Heavy Metal - United-Kingdom

Ossian

Heavy Metal - Hungary

OSSY

Heavy Metal - Finland

Ossyris

Heavy Metal - Spain

Ostrogoth

Heavy Metal - Belgium

Osvajaci

Heavy Metal - Serbia

Other Side

Heavy Metal - Argentina

Other View

Heavy Metal - Italy

Other World (ITA)

Heavy Metal - Italy

Outburst (FIN)

Heavy Metal - Finland

Outcast (GER)

Heavy Metal - Germany