1 Omashu City
1 Opal Palace
1 Orzhov Guildgate
1 Overflowing Basin
1 O'aka, Traveling Merchant
1 Oakenform
1 Oashra Cultivator
1 Oasis Gardener
1 Oath of Chandra
1 Oblivion Strike
1 Oblivion's Hunger
1 Obscura Charm
1 Observed Stasis
1 Obsessive Pursuit
1 Obsessive Skinner
1 Obsessive Stitcher
1 Obstinate Baloth
1 Obstinate Gargoyle
1 Obyra's Attendants // Desperate Parry
1 Ochran Assassin
1 Octo Opus
1 Octoprophet
1 Octopus Form
1 Odric, Blood-Cursed
1 Offspring's Revenge
1 Oggyar Battle-Seer
1 Ogre Jailbreaker
1 Oil-Gorger Troll
1 Oji, the Exquisite Blade
1 Ojutai Interceptor
1 Oketra's Attendant
1 Okiba Reckoner Raid // Nezumi Road Captain
1 Oko's Hospitality
1 Oliphaunt
1 Olivia's Bloodsworn
1 Olivia's Dragoon
1 Olivia's Midnight Ambush
1 Ollenbock Escort
1 Oltec Archaeologists
1 Oltec Cloud Guard
1 Omega Myr
1 Omega, Heartless Evolution
1 Omen Hawker
1 Omen of the Dead
1 Omen of the Hunt
1 Omen of the Sun
1 Omenport Vigilante
1 Omenspeaker
1 Ominous Seas
1 Omniclown Colossus // Pie-roclasm
1 Onakke Ogre
1 Ondu Champion
1 Ondu Giant
1 Ondu Greathorn
1 Ondu Rising
1 Ondu War Cleric
1 One-Clown Band
1 Onward // Victory
1 Oona's Gatewarden
1 Oona's Grace
1 Opaline Unicorn
1 Open into Wonder
1 Open the Graves
1 Opera Love Song
1 Ophidian
1 Opportunity
1 Oppressive Rays
1 Oracle of Dust
1 Oracle of Tragedy
1 Oran-Rief Invoker
1 Oran-Rief Recluse
1 Orazca Frillback
1 Orazca Relic
1 Orb of Dragonkind
1 Orbital Plunge
1 Orchard Spirit
1 Orcish Medicine
1 Orcish Oriflamme
1 Orcish Paratroopers
1 Orcus, Prince of Undeath
1 Ordeal of Erebos
1 Order of the Mirror // Order of the Alabaster Host
1 Oreplate Pangolin
1 Oreskos Explorer
1 Oreskos Sun Guide
1 Oreskos Swiftclaw
1 Organ Hoarder
1 Origin of Metalbending
1 Ornamental Courage
1 Ornery Dilophosaur
1 Ornery Kudu
1 Ornitharch
1 Ornithopter
1 Orthodoxy Enforcer
1 Orzhov Advokist
1 Orzhov Keyrune
1 Orzhov Locket
1 Ossuary Rats
1 Ostrich-Horse
1 Oswald Fiddlebender
1 Oteclan Landmark // Oteclan Levitator
1 Otherworldly Gaze
1 Otherworldly Journey
1 Otherworldly Outburst
1 Otter-Penguin
1 Our Market Research Shows That Players Like Really Long Card Names So We Made this Card to Have the Absolute Longest Card Name Ever Elemental
1 Ouroboroid
1 Out Cold
1 Out of the Way
1 Outland Boar
1 Outland Colossus
1 Outlaws' Fury
1 Outnumber
1 Outpost Siege
1 Outrider of Jhess
1 Ovalchase Dragster
1 Overblaze
1 Overclocked Electromancer
1 Overgrowth
1 Overgrowth Elemental
1 Overkill
1 Overrun
1 Overseer of the Damned
1 Overwhelm
1 Overwhelming Remorse
1 Owlbear
1 Oxidda Finisher
1 Oxidda Golem
1 Ozai, the Phoenix King
1 Ozai's Cruelty
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