| 77 | Unfathomable Truths | Drew Tucker | Blue | C | Modern Horizons 3 |
| 8 | Unfinished Business | Mark Zug | White | R | Wilds of Eldraine Commander |
| 44 | Unfinished Business | Mark Zug | White | R | Wilds of Eldraine Commander |
| 111 | Unflinching Courage | Mike Bierek | White/Green | U | Dragon's Maze |
| 192 | Unflinching Courage | Mike Bierek | White/Green | U | Commander 2018 |
| 197 | Unflinching Courage | Mike Bierek | White/Green | U | Modern Masters 2017 Edition |
| 230 | Unflinching Courage | Mike Bierek | White/Green | U | Battlebond |
| 71 | Unforge | Kev Walker | Red | C | Darksteel |
| 127 | Unforgiving One | Fariba Khamseh | Black | U | Kamigawa: Neon Dynasty |
| 111 | Unfortunate Accident | Josiah "Jo" Cameron | Black | U | Outlaws of Thunder Junction |
| 172 | Unfriendly Fire | Josu Hernaiz | Red | C | Ixalan |
| Unfulfilled Desires | D. Alexander Gregory | Blue/Black | R | Mirage |
| 45 | Unglued Pea-Brained Dinosaur | Larissa Hasenheit, Mina Jeon, Daria Sergeyeva, Sam Burley | | C | Unfinity |
| 13 | Unhallowed Cathar | Ryan Pancoast | Black | C | Dark Ascension |
| 64 | Unhallowed Pact | Volkan Baga | Black | C | Duel Decks: Nissa vs. Ob Nixilis |
| 124 | Unhallowed Pact | Volkan Baga | Black | C | Avacyn Restored |
| 131 | Unhallowed Pact | Volkan Baga | Black | C | Magic: The Gathering—Conspiracy |
| 135 | Unhallowed Phalanx | Nicholas Gregory | Black | C | Innistrad: Crimson Vow |
| 87 | Unhinge | Keith Garletts | Black | C | Torment |
| 39 | Unhinged Beast Hunt | Larissa Hasenheit, Mina Jeon, Daria Sergeyeva, Sam Burley | | C | Unfinity |
| 118 | Unholy Annex | Matteo Bassini | Black | R | Duskmourn: House of Horror |
| 339 | Unholy Annex | Alexis Ziritt | Black | R | Duskmourn: House of Horror |
| Unholy Citadel | Mark Poole | | U | Legends |
| 8 | Unholy Fiend | Igor Kieryluk | Black | U | Innistrad |
| 327 | Unholy Grotto | John Avon | | R | Onslaught |
| 71 | Unholy Heat | Josh Hass | Red | M | Special Guests |
| 145 | Unholy Heat | Kari Christensen | Red | C | Modern Horizons 2 |
| 182 | Unholy Heat | Kari Christensen | Red | C | Outlaws of Thunder Junction Commander |
| 120 | Unholy Hunger | Lius Lasahido | Black | C | Ultimate Masters |
| 125 | Unholy Hunger | Lius Lasahido | Black | C | Magic Origins |
| 119 | Unholy Indenture | Seb McKinnon | Black | C | Core Set 2020 |
| 41 | Unholy Officiant | Campbell White | White | C | Innistrad: Crimson Vow |
| 286 | Unholy Officiant | Jason A. Engle | White | C | Innistrad: Crimson Vow |
| Unholy Strength | Tom Kyffin | Black | C | Fifth Edition |
| Unholy Strength | Douglas Shuler | Black | C | Fourth Edition |
| Unholy Strength | Douglas Shuler | Black | C | Revised Edition |
| Unholy Strength | Douglas Schuler | Black | C | Unlimited Edition |
| Unholy Strength | Douglas Schuler | Black | C | Limited Edition Beta |
| Unholy Strength | Douglas Schuler | Black | C | Limited Edition Alpha |
| 47 | Unholy Strength | Terese Nielsen | Black | C | Duel Decks Anthology, Divine vs. Demonic |
| 47 | Unholy Strength | Terese Nielsen | Black | C | Duel Decks: Divine vs. Demonic |
| 116 | Unholy Strength | Terese Nielsen | Black | C | Magic 2010 |
| 119 | Unholy Strength | Terese Nielsen | Black | C | Magic 2011 |
| 168 | Unholy Strength | Puddnhead | Black | C | Ninth Edition |
| 168 | Unholy Strength | Gary Ruddell | Black | C | Seventh Edition |
| 169 | Unholy Strength | Puddnhead | Black | C | Eighth Edition |
| 185 | Unholy Strength | Terese Nielsen | Black | C | Tenth Edition |
| 110 | Unicycle (playtest) | Ari Nieh | | C | Mystery Booster |
| 37 | Unidentified Hovership | Jana Heidersdorf | White | R | Duskmourn: House of Horror |
| 305 | Unidentified Hovership | Calder Moore | White | R | Duskmourn: House of Horror |
| 53 | Unified Front | Dan Scott | White | U | Battle for Zendikar |
| 58 | Unified Strike | Dave Dorman | White | C | Onslaught |
| 92 | Unified Will | Matt Cavotta | Blue | U | Rise of the Eldrazi |
| 112 | Unifying Theory | Ron Spears | Blue | R | Odyssey |
| 94 | Unimpeded Trespasser | Dan Scott | Blue | U | Shadows over Innistrad |
| 94 | Uninvited Geist | Dan Scott | Blue | U | Shadows over Innistrad |
| 31 | Union of the Third Path | Robin Olausson | White | C | The Brothers' War |
| 38 | Unique Charmed Pants | Larissa Hasenheit, Mina Jeon, Daria Sergeyeva, Sam Burley | | C | Unfinity |
| 15 | Unite the Coalition | Nestor Ossandon Leal | White/Blue/Black/Red/Green | R | Dominaria United Commander |
| 91 | Unite the Coalition | Nestor Ossandon Leal | White/Blue/Black/Red/Green | R | Dominaria United Commander |
| 66 | Unity of Purpose | Jason Felix | Blue | U | Oath of the Gatewatch |
| 235 | Universal Automaton | Ben Maier | | C | Modern Horizons |
| 803 | Universal Automaton | Ben Maier | | C | Jumpstart 2022 |
| 178 | Universal Solvent | Christopher Moeller | | C | Aether Revolt |
| 273 | Universal Solvent | Christopher Moeller | | C | Kaladesh Remastered |
| 342 | Universal Solvent | Joe Slucher | | C | Commander Legends: Battle for Baldur's Gate |
| 347 | Universal Solvent | Christopher Moeller | | C | Commander Legends |
| 804 | Universal Solvent | Christopher Moeller | | C | Jumpstart 2022 |
| 17 | Universal Surveillance | Aaron J. Riley | Blue | R | Kamigawa: Neon Dynasty Commander |
| 54 | Universal Surveillance | Aaron J. Riley | Blue | R | Kamigawa: Neon Dynasty Commander |
| 181 | Unknown Shores | Jung Park | | C | Oath of the Gatewatch |
| 229 | Unknown Shores | Seb McKinnon | | C | Theros |
| 249 | Unknown Shores | Adam Paquette | | C | Theros Beyond Death |
| 259 | Unknown Shores | Rob Alexander | | C | Ixalan |
| 62 | Unlawful Entry | Francis Tneh | Blue | C | Unfinity |
| 170 | Unleash Fury | Izzy | Red | U | Core Set 2021 |
| 155 | Unleash Shell | Campbell White | Red | C | The Brothers' War |
| 229 | Unleash the Inferno | Zoltan Boros | Black/Red/Green | R | Streets of New Capenna |
| 337 | Unleash the Inferno | Justin & Alexis Hernandez | Black/Red/Green | R | Streets of New Capenna |
| 402 | Unleash the Inferno | Justin & Alexis Hernandez | Black/Red/Green | R | Streets of New Capenna |
| 187 | Unlicensed Disintegration | Izzy | Black/Red | U | Kaladesh |
| 211 | Unlicensed Disintegration | Izzy | Black/Red | U | Kaladesh Remastered |
| 224 | Unlicensed Disintegration | Izzy | Black/Red | U | Double Masters |
| 64 | Unlicensed Hearse | Sean Murray | | R | Outlaws of Thunder Junction Breaking News |
| 246 | Unlicensed Hearse | Chris Seaman | | R | Streets of New Capenna |
| 440 | Unlicensed Hearse | Chris Seaman | | R | Streets of New Capenna |
| 64 | Unlikely Aid | Viktor Titov | Black | C | Arena Base Set |
| 103 | Unlikely Aid | Randy Vargas | Black | C | Ikoria: Lair of Behemoths |
| 109 | Unlikely Aid | Viktor Titov | Black | C | War of the Spark |
| Unlikely Alliance | Phil Foglio | White | U | Alliances |
| 61 | Unlikely Meeting | Elizabeth Peiró | Blue | R | Doctor Who Commander |
| 56 | Unliving Psychopath | Greg Staples | Black | R | Dissension |
| 82 | Unlucky Drop | Patrik Hell | Blue | C | The Lost Caverns of Ixalan |
| 128 | Unlucky Witness | Tyler Walpole | Red | U | Streets of New Capenna |
| 27 | Unmake | Steven Belledin | White/Black | C | Duel Decks: Sorin vs. Tibalt |
| 96 | Unmake | Steven Belledin | White/Black | C | Eventide |
| 98 | Unmake | Steven Belledin | White/Black | C | Archenemy |
| 120 | Unmake the Graves | Aaron Miller | Black | C | Magic 2015 Core Set |
| 106 | Unmarked Grave | James Paick | Black | R | Modern Horizons 2 |
| 453 | Unmarked Grave | James Paick | Black | R | Modern Horizons 2 |
| 15 | Unmask | rk post | Black | M | From the Vault: Lore |
| 168 | Unmask | rk post | Black | R | Mercadian Masques |
| 212 | Unmoored Ego | Volkan Baga | Blue/Black | R | Guilds of Ravnica |
| 168 | Unnatural Aggression | James Ryman | Green | C | Battle for Zendikar |
| 737 | Unnatural Aggression | James Ryman | Green | C | Jumpstart 2022 |
| 80 | Unnatural Endurance | Mathias Kollros | Black | C | Oath of the Gatewatch |
| 62 | Unnatural Growth | Francoyovich | Green | R | Wilds of Eldraine Enchanting Tales |
| 206 | Unnatural Growth | Svetlin Velinov | Green | R | Innistrad: Midnight Hunt |
| 245 | Unnatural Growth | Svetlin Velinov | Green | R | Bloomburrow Commander |
| 365 | Unnatural Growth | Svetlin Velinov | Green | R | Innistrad: Midnight Hunt |
| 169 | Unnatural Hunger | Jeff Miracola | Black | R | Mercadian Masques |
| 247 | Unnatural Moonrise | Ryan Pancoast | Red/Green | U | Innistrad: Midnight Hunt |
| 93 | Unnatural Predation | Shelly Wan | Green | C | Mirrodin Besieged |
| 191 | Unnatural Restoration | Jeremy Wilson | Green | U | Phyrexia: All Will Be One |
| 32 | Unnatural Selection | Kev Walker | Blue | R | Apocalypse |
| 197 | Unnatural Speed | Wayne Reynolds | Red | C | Champions of Kamigawa |
| Unnerve | Terese Nielsen | Black | C | Battle Royale Box Set |
| 81 | Unnerve | Terese Nielsen | Black | C | Commander Anthology 2018 |
| 105 | Unnerve | Terese Nielsen | Black | C | Magic: The Gathering-Commander |
| 150 | Unnerve | Terese Nielsen | Black | C | Conspiracy: Take the Crown |
| 162 | Unnerve | Terese Nielsen | Black | C | Urza's Saga |
| 114 | Unnerving Assault | Ron Spencer | Blue/Red | U | Eventide |
| 80 | Unnerving Grasp | Jeremy Wilson | Blue | U | Duskmourn: House of Horror |
| 139 | Unpredictable Cyclone | Noah Bradley | Red | R | Ikoria: Lair of Behemoths |
| 23 | Unquenchable Fury | Livia Prima | Red | R | Kamigawa: Neon Dynasty Commander |
| 63 | Unquenchable Fury | Livia Prima | Red | R | Kamigawa: Neon Dynasty Commander |
| 53 | Unquenchable Thirst | Jeremy Wilson | Blue | C | Hour of Devastation |
| 86 | Unquenchable Thirst | Jeremy Wilson | Blue | C | Amonkhet Remastered |
| 31 | Unquestioned Authority | Alex Horley-Orlandelli | White | U | Judgment |
| 78 | Unquestioned Authority | Zoltan Boros | White | U | Commander 2018 |
| 85 | Unquestioned Authority | Zoltan Boros | White | U | Magic: The Gathering—Conspiracy |
| 260 | Unquestioned Authority | Alex Horley-Orlandelli | White | U | Jumpstart 2022 |
| 389 | Unquestioned Authority | Zoltan Boros | White | U | Commander Legends |
| 143 | Unravel the Aether | Jung Park | Green | U | Born of the Gods |
| 147 | Unraveling Mummy | Tomasz Jedruszek | White/Black | U | Hour of Devastation |
| 156 | Unruly Catapult | Vincent Christiaens | Red | C | Wilds of Eldraine |
| 50 | Unruly Krasis | Billy Christian | Blue/Green | R | Ravnica Clue Edition |
| 39 | Unruly Mob | Ryan Pancoast | White | C | Innistrad |
| 40 | Unruly Mob | Ryan Pancoast | White | C | Innistrad: Midnight Hunt |
| 47 | Unruly Mob | Ryan Pancoast | White | C | Shadows over Innistrad |
| 13 | Unsanctioned Ancient Juggler | Larissa Hasenheit, Mina Jeon, Daria Sergeyeva, Sam Burley | | C | Unfinity |
| 109 | Unscrupulous Agent | Michal Ivan | Black | C | Murders at Karlov Manor |
| 112 | Unscrupulous Contractor | Mila Pesic | Black | U | Outlaws of Thunder Junction |
| 114 | Unscythe, Killer of Kings | Karl Kopinski | Blue/Black/Red | R | Alara Reborn |
| 128 | Unseal the Necropolis | Isis | Black | C | March of the Machine |
| Unseen Walker | Alan Rabinowitz | Green | U | Mirage |
| 262 | Unseen Walker | Alan Rabinowitz | Green | U | Classic Sixth Edition |
| 216 | Unsettled Mariner | John Stanko | White/Blue | R | Modern Horizons |
| 38 | Unsettling Twins | Lauren K. Cannon | White | C | Duskmourn: House of Horror |
| 29 | Unshakable Tail | Sean Murray | Black | R | Murders at Karlov Manor Commander |
| 339 | Unshakable Tail | Sean Murray | Black | R | Murders at Karlov Manor Commander |
| 79 | Unspeakable Symbol | Arnie Swekel | Black | U | Scourge |
| 142 | Unstable Amulet | José Parodi | Red | U | Modern Horizons 3 |
| 421 | Unstable Amulet | José Parodi | Red | U | Modern Horizons 3 |
| 153 | Unstable Footing | Nic Klein | Red | U | Zendikar |
| 145 | Unstable Frontier | John Avon | | U | Conflux |
| 41 | Unstable Glyphbridge | Bastien Grivet | White | R | The Lost Caverns of Ixalan |
| 358 | Unstable Glyphbridge | Bastien Grivet | White | R | The Lost Caverns of Ixalan |
| 115 | Unstable Hulk | Ron Spencer | Red | R | Legions |
| Unstable Mutation | Charles Gillespie | Blue | C | Fifth Edition |
| Unstable Mutation | Douglas Shuler | Blue | C | Fourth Edition |
| Unstable Mutation | Douglas Shuler | Blue | C | Revised Edition |
| Unstable Mutation | Douglas Shuler | Blue | C | Arabian Nights |
| 33 | Unstable Mutation | Douglas Shuler | Blue | S | Time Spiral "Timeshifted" |
| 80 | Unstable Mutation | Slawomir Maniak | Blue | U | Ultimate Masters |
| 58 | Unstable Obelisk | William Wu | | U | Commander 2014 |
| 170 | Unstable Obelisk | William Wu | | U | Innistrad: Crimson Vow Commander |
| 220 | Unstable Obelisk | William Wu | | U | Adventures in the Forgotten Realms Commander |
| 227 | Unstable Obelisk | William Wu | | U | Commander 2018 |
| 227 | Unstable Obelisk | William Wu | | U | Commander Anthology 2018 |
| 229 | Unstable Obelisk | William Wu | | U | Commander 2017 |
| 260 | Unstable Obelisk | Johannes Mücke | | C | Warhammer 40,000 Commander |
| 272 | Unstable Obelisk | William Wu | | U | Commander 2021 |
| 416 | Unstable Obelisk | William Wu | | C | Commander Masters |
| 489 | Unstable Obelisk | William Wu | | U | Jumpstart |
| 47 | Unstable Robot Dragon | Larissa Hasenheit, Mina Jeon, Daria Sergeyeva, Sam Burley | | C | Unfinity |
| Unstable Shapeshifter | Terese Nielsen | Blue | R | Tempest |
| 137 | Unstoppable Ash | Brian Snoddy | Green | R | Morningtide |
| 169 | Unstoppable Ogre | Xavier Ribeiro | Red | C | Kamigawa: Neon Dynasty |
| 119 | Unstoppable Slasher | Maxime Minard | Black | R | Duskmourn: House of Horror |
| 294 | Unstoppable Slasher | Maxime Minard | Black | R | Duskmourn: House of Horror |
| 312 | Unstoppable Slasher | SchmandrewART | Black | R | Duskmourn: House of Horror |
| 79 | Unsubstantiate | Victor Adame Minguez | Blue | U | Eldritch Moon |
| 82 | Unsubstantiate | Victor Adame Minguez | Blue | U | Core Set 2021 |