| Name | Cost | Price |
|---|---|---|
| Ordruun Veteran | $0.03 | |
| Oread of Mountain's Blaze | $0.20 | |
| Oreskos Explorer | $0.18 | |
| Oreskos Sun Guide | $0.19 | |
| Oreskos Swiftclaw | $0.06 | |
| Organ Harvest | $0.37 | |
| Organic Extinction | $1.91 | |
| Orgg | $0.99 | |
| Origin of Metalbending | $0.33 | |
| Origin of Spider-Man | — | |
| Origin of the Hidden Ones | $0.19 | |
| Orim's Chant | $10.38 | |
| Orim's Prayer | $0.50 | |
| Orim's Thunder | $0.05 | |
| Orim's Touch | $0.04 | |
| Oriq Loremage | $0.57 | |
| Ornery Dilophosaur | $0.19 | |
| Ornery Goblin | $0.08 | |
| Ornery Tumblewagg | $0.38 | |
| Ornithopter | $0.27 | |
| Ornithopter of Paradise | $0.41 | |
| Orochi Merge-Keeper | $0.27 | |
| Oros, the Avenger | — | |
| Orthion, Hero of Lavabrink | $6.32 |