| Nut Collector | ODY-259 |
| Nykthos Paragon | MH2-22 |
| Nykthos, Shrine to Nyx | THS-223 |
| Nylea, God of the Hunt | THS-166 |
| Nylea's Presence | THS-169 |
| Nyx Weaver | JOU-153 |
| Nyx-Fleece Ram | A25-26 |
| O-Naginata | SOK-157 |
| Oaken Brawler | LRW-33 |
| Oakgnarl Warrior | DDR-15 |
| Oakhame Adversary | ELD-167 |
| Oath of Lieges | EXO-11 |
| Oath of Nissa | OGW-140 |
| Oath of Scholars | EXO-42 |
| Oathsworn Giant | RAV-27 |
| Ob Nixilis, the Fallen | IMA-101 |
| Obelisk Spider | HOU-141 |
| Obliterate | INV-156 |
| Oblivion Ring | LRW-34 |
| Oblivion Strike | OGW-75 |
| Obsessive Stitcher | M21-223 |
| Ochran Assassin | GRN-194 |
| Octopus Umbra | C18-11 |
| Odds // Ends | DIS-153 |
| Odric, Lunarch Marshal | SOI-31 |
| Odric, Lunarch Marshal | DMC-103 |
| Odric, Master Tactician | M13-23 |
| Ogre Arsonist | P02-110 |
| Ogre Gatecrasher | DIS-67 |
| Ohran Frostfang | C19-33 |
| Ojutai Interceptor | DTK-66 |
| Ojutai's Breath | DTK-67 |
| Oketra's Monument | AKH-233 |
| Okiba-Gang Shinobi | PCA-35 |
| Okina, Temple to the Grandfathers | CHK-280 |
| Oko, the Trickster | ELD-309 |
| Old Ghastbark | SHM-232 |
| Old Gnawbone | AFR-197 |
| Olivia, Mobilized for War | SOI-248 |
| Olivia's Bloodsworn | SOI-127 |
| Oloro, Ageless Ascetic | C13-203 |
| Omen | POR-62 |
| Omen of the Sea | THB-58 |
| Omen of the Sun | THB-30 |
| Omenspeaker | BBD-125 |
| Ominous Seas | IKO-61 |
| Omnath, Locus of Rage | BFZ-217 |
| On Serra's Wings | DOM-28 |
| Onakke Ogre | M19-153 |
| Once Upon a Time | ELD-169 |