- Of The Fallen (Black Metal-USA)
- Orion, The Fallen (Grunge-Portugal)
- One Of Them (Thrash Metal-Brazil)
- Order Of Thelema (Doom Black-USA)
- Oneheadedman (Metal-Hungary)
- One Of These Days (Grindcore-Greece)
- Our Fallen (Deathcore-Australia)
- Onfall (Deathcore-Italy)
- Order Of The Nameless Ones (Black Death-USA)