| One Dozen EyesSalvat 2005 · K40 | Salvat 2005 | K40 | Uncommon | €0.87 |
| One Dozen EyesDuel Decks: Mirrodin Pure vs. New Phyrexia · 80 | Duel Decks: Mirrodin Pure vs. New Phyrexia | 80 | Uncommon | — |
| OneirophageJumpstart · 162 | Jumpstart | 162 | Uncommon | €0.16 |
| OneirophageJumpstart 2022 · 331 | Jumpstart 2022 | 331 | Uncommon | €0.18 |
| OneirophageFoundations Jumpstart · 337 | Foundations Jumpstart | 337 | Uncommon | $0.33 |
| OneirophageModern Horizons · 60 | Modern Horizons | 60 | Uncommon | €0.16 |
| OneirophageThe List Tokens · MH1-60 | The List Tokens | MH1-60 | Uncommon | €0.07 |
| One Thousand LashesRNA Guild Kit · 41 | RNA Guild Kit | 41 | Uncommon | €0.20 |
| One Thousand LashesGatecrash · 183 | Gatecrash | 183 | Uncommon | $0.11 |
| One with NatureScourge · 125 | Scourge | 125 | Uncommon | €1.86 |
| One with NatureThe List Tokens · SCG-125 | The List Tokens | SCG-125 | Uncommon | $1.14 |
| One with the StarsTheros Beyond Death · 59 | Theros Beyond Death | 59 | Uncommon | €0.10 |
| Ongoing InvestigationMurders at Karlov Manor Commander · 114 | Murders at Karlov Manor Commander | 114 | Uncommon | €0.17 |
| Ongoing InvestigationShadows over Innistrad · 77 | Shadows over Innistrad | 77 | Uncommon | €0.10 |
| Ongoing InvestigationShadows over Innistrad Remastered · 84 | Shadows over Innistrad Remastered | 84 | Uncommon | — |
| Oni-Cult AnvilThe Brothers' War Commander · 127 | The Brothers' War Commander | 127 | Uncommon | $0.23 |
| Oni-Cult AnvilKamigawa: Neon Dynasty · 230 | Kamigawa: Neon Dynasty | 230 | Uncommon | €0.14 |
| Oni of Wild PlacesCommander Anthology · 85 | Commander Anthology | 85 | Uncommon | €0.09 |
| Oni of Wild PlacesCommander 2011 · 130 | Commander 2011 | 130 | Uncommon | €0.10 |
| Oni of Wild PlacesDuel Decks: Speed vs. Cunning Tokens · 19 | Duel Decks: Speed vs. Cunning Tokens | 19 | Uncommon | €0.08 |
| Oni of Wild PlacesSaviors of Kamigawa · 108 | Saviors of Kamigawa | 108 | Uncommon | €0.10 |
| Oni PossessionChampions of Kamigawa · 135 | Champions of Kamigawa | 135 | Uncommon | €0.14 |
| Oni PossessionDuel Decks: Divine vs. Demonic · 51 | Duel Decks: Divine vs. Demonic | 51 | Uncommon | €0.08 |
| Oni PossessionDuel Decks Anthology: Divine vs. Demonic · 51 | Duel Decks Anthology: Divine vs. Demonic | 51 | Uncommon | €0.15 |
| On Serra's WingsCommander Legends · 380 | Commander Legends | 380 | Uncommon | €0.05 |
| On Serra's WingsDominaria · 28 | Dominaria | 28 | Uncommon | $0.21 |
| On Serra's WingsThe List Tokens · DOM-28 | The List Tokens | DOM-28 | Uncommon | €0.14 |
| OnuletAntiquities · 59 | Antiquities | 59 | Uncommon | $1.91 |
| Onward // VictoryAmonkhet · 218 | Amonkhet | 218 | Uncommon | €0.07 |
| Onward // VictoryAmonkhet Remastered · 250 | Amonkhet Remastered | 250 | Uncommon | — |
| Onyx MageMagic 2012 · 103 | Magic 2012 | 103 | Uncommon | €0.20 |
| Onyx TalismanIce Age · 331 | Ice Age | 331 | Uncommon | €0.34 |
| Oona's BlackguardJumpstart · 261 | Jumpstart | 261 | Uncommon | €0.35 |
| Oona's BlackguardMorningtide · 72 | Morningtide | 72 | Uncommon | €0.66 |
| Oona's BlackguardZendikar Rising Commander · 51 | Zendikar Rising Commander | 51 | Uncommon | $0.35 |
| Oona's BlackguardMagic Online Promos · 32535 | Magic Online Promos | 32535 | Uncommon | — |
| Ooze PatrolAetherdrift · 172 | Aetherdrift | 172 | Uncommon | €0.03 |
| Ooze SpillTeenage Mutant Ninja Turtles · 48 | Teenage Mutant Ninja Turtles | 48 | Uncommon | €0.09 |
| Opal AcrolithUrza's Saga · 22 | Urza's Saga | 22 | Uncommon | €0.21 |
| Opaline SliverTime Spiral · 244 | Time Spiral | 244 | Uncommon | €0.55 |
| Open into WonderAmonkhet · 64 | Amonkhet | 64 | Uncommon | $0.22 |
| Open into WonderZendikar Rising Commander · 34 | Zendikar Rising Commander | 34 | Uncommon | €0.16 |
| Open the ArmoryCommander Legends · 34 | Commander Legends | 34 | Uncommon | €2.32 |
| Open the ArmoryShadows over Innistrad · 32 | Shadows over Innistrad | 32 | Uncommon | $2.58 |
| Open the ArmoryPioneer Masters · 360 | Pioneer Masters | 360 | Uncommon | — |
| Opera Love SongFinal Fantasy · 147 | Final Fantasy | 147 | Uncommon | €0.15 |
| OpportunistTempest · 194 | Tempest | 194 | Uncommon | €0.13 |
| OpportunitySeventh Edition · 91 | Seventh Edition | 91 | Uncommon | $0.21 |
| OpportunitySeventh Edition · 91★ | Seventh Edition | 91★ | Uncommon | $0.21 |
| OpportunityBattlebond · 126 | Battlebond | 126 | Uncommon | €0.08 |