| Overseer of the Damned (5 variants) | 132 |
| Otherworldly Gaze (5 variants) | 115 |
| Otherworldly Escort (5 variants) | 323 |
| Otherworldly Escort (5 variants) | 12 |
| Orzhov Advokist (5 variants) | 77 |
| Organic Extinction (5 variants) | 76 |
| Ongoing Investigation (5 variants) | 114 |
| On the Trail (5 variants) | 349 |
| On the Trail (5 variants) | 39 |
| Ohran Frostfang (5 variants) | 180 |
| Obscuring Aether (5 variants) | 179 |
| Notion Rain (5 variants) | 217 |
| Nightveil Sprite (5 variants) | 113 |
| Nettlecyst (5 variants) | 233 |
| Nelly Borca, Impulsive Accuser | 52 |
| Nelly Borca, Impulsive Accuser (10 variants) | 318 |
| Nelly Borca, Impulsive Accuser (5 variants) | 4 |
| Neheb, the Eternal (5 variants) | 158 |
| Needle Spires (5 variants) | 278 |
| Necromancy (5 variants) | 131 |
| Nature's Lore (5 variants) | 178 |
| Nantuko Vigilante (5 variants) | 177 |
| Nadir Kraken (5 variants) | 112 |
| Mystic Sanctuary (5 variants) | 277 |
| Myriad Landscape (5 variants) | 276 |
| Mulldrifter (5 variants) | 111 |
| Mosswort Bridge (5 variants) | 275 |
| Mossfire Valley (5 variants) | 274 |
| Morska, Undersea Sleuth (10 variants) | 317 |
| Morska, Undersea Sleuth | 51 |
| Morska, Undersea Sleuth (5 variants) | 3 |
| Mob Verdict (5 variants) | 343 |
| Mob Verdict (5 variants) | 33 |
| Mission Briefing (5 variants) | 110 |
| Mirror Entity (5 variants) | 75 |
| Mirko, Obsessive Theorist (10 variants) | 316 |
| Mirko, Obsessive Theorist (5 variants) | 2 |
| Mirko, Obsessive Theorist | 50 |
| Mind Stone (5 variants) | 232 |
| Merchant of Truth (5 variants) | 322 |
| Merchant of Truth (5 variants) | 11 |
| Mechanized Production (5 variants) | 109 |
| Mastery of the Unseen (5 variants) | 74 |
| Master of Pearls (5 variants) | 73 |
| Master of Death (5 variants) | 216 |
| Massacre Wurm (5 variants) | 130 |
| Marvo, Deep Operative (10 variants) | 315 |
| Marvo, Deep Operative (5 variants) | 7 |
| Martial Impetus (5 variants) | 72 |
| Loran of the Third Path (5 variants) | 71 |