- Orichalcos Gigas
- Orichalcos Kyutora
- Orichalcos Malevolence
- Otohime
- Over Boost
- Overlay Eater
- Oxygeddon
- Paladin of White Dragon
- Panther Warrior
- Parasite Caterpillar
- Parasite Paracide
- Parrot Dragon
- Paternal Junk
- Patroid
- Pendulum Machine
- Penguin Torpedo
- Perfect Machine King
- Perfectly Ultimate Great Moth
- Performapal Hip Hippo
- Performapal Skeeter Skimmer
- Performapal Sword Fish
- Performapal Whip Snake
- Petit Angel
- Petit Dragon