| Name | Cost | Price |
|---|---|---|
| Oni Possession | $0.17 | |
| On Serra's Wings | $0.19 | |
| Onslaught | $0.16 | |
| On the Job | $0.04 | |
| On the Trail | $4.23 | |
| Onulet | $0.51 | |
| Onward // Victory | $0.18 | |
| Onyx Goblet | $0.13 | |
| Oona, Queen of the Fae | $1.42 | |
| Oona's Blackguard | $0.47 | |
| Oona's Grace | $0.17 | |
| Oozeavite | — | |
| Ooze Patrol | $0.23 | |
| Opal Caryatid | $0.13 | |
| Opal Champion | $0.14 | |
| Opalescence | $15.58 | |
| Opaline Bracers | $0.13 | |
| Opaline Unicorn | $0.25 | |
| Opal Lake Gatekeepers | $0.10 | |
| Opal Palace | $0.24 | |
| Opal Titan | $0.48 | |
| Open Fire | $0.06 | |
| Opening Ceremony | $0.34 | |
| Open into Wonder | $0.30 |