| Kruin Outlaw // Terror of Kruin PassShadows of the Past · 42 | Shadows of the Past | 42 | Rare | — |
| Kudo, King Among BearsModern Horizons 3 · 192 | Modern Horizons 3 | 192 | Rare | €0.15 |
| Kudo, King Among BearsModern Horizons 3 · 376 | Modern Horizons 3 | 376 | Rare | €0.51 |
| Kudo, King Among BearsModern Horizons 3 · 432 | Modern Horizons 3 | 432 | Rare | €0.33 |
| Kudo, King Among BearsModern Horizons 3 · 490 | Modern Horizons 3 | 490 | Rare | €0.63 |
| Kudo, King Among BearsModern Horizons 3 Promos · 192s | Modern Horizons 3 Promos | 192s | Rare | €0.92 |
| KudzuUnlimited Edition · 205 | Unlimited Edition | 205 | Rare | €13.24 |
| KudzuRevised Edition · 205 | Revised Edition | 205 | Rare | $1.57 |
| Kudzu30th Anniversary Edition · 200 | 30th Anniversary Edition | 200 | Rare | €15.00 |
| Kudzu30th Anniversary Edition · 497 | 30th Anniversary Edition | 497 | Rare | $65.75 |
| KudzuCollectors' Edition · 205 | Collectors' Edition | 205 | Rare | €1.56 |
| KudzuIntl. Collectors' Edition · 205 | Intl. Collectors' Edition | 205 | Rare | €1.81 |
| KudzuForeign Black Border · 205 | Foreign Black Border | 205 | Rare | €3.48 |
| KudzuLimited Edition Alpha · 204 | Limited Edition Alpha | 204 | Rare | €451.82 |
| KudzuLimited Edition Beta · 205 | Limited Edition Beta | 205 | Rare | $148.50 |
| KudzuSummer Magic / Edgar · 205 | Summer Magic / Edgar | 205 | Rare | — |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 232 | Final Fantasy | 232 | Rare | €1.04 |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 232† | Final Fantasy | 232† | Rare | — |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 399 | Final Fantasy | 399 | Rare | $4.54 |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 399† | Final Fantasy | 399† | Rare | — |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 497 | Final Fantasy | 497 | Rare | €4.61 |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 497† | Final Fantasy | 497† | Rare | — |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 544 | Final Fantasy | 544 | Rare | €31.40 |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy · 544† | Final Fantasy | 544† | Rare | — |
| Kuja, Genome Sorcerer // Trance Kuja, Fate DefiedFinal Fantasy Promos · 232s | Final Fantasy Promos | 232s | Rare | $12.03 |
| Kukemssa PiratesMirage · 71 | Mirage | 71 | Rare | €1.46 |
| Kuldotha ForgemasterDouble Masters · 266 | Double Masters | 266 | Rare | €5.16 |
| Kuldotha ForgemasterScars of Mirrodin · 169 | Scars of Mirrodin | 169 | Rare | €4.68 |
| Kuldotha ForgemasterDuel Decks: Mirrodin Pure vs. New Phyrexia · 14 | Duel Decks: Mirrodin Pure vs. New Phyrexia | 14 | Rare | — |
| Kuldotha PhoenixMedia and Collaboration Promos · 2010-5 | Media and Collaboration Promos | 2010-5 | Rare | €0.25 |
| Kuldotha PhoenixScars of Mirrodin · 95 | Scars of Mirrodin | 95 | Rare | $0.20 |
| Kumano, Master YamabushiChampions of Kamigawa · 176 | Champions of Kamigawa | 176 | Rare | €0.25 |
| Kumena's AwakeningRivals of Ixalan Promos · 42s | Rivals of Ixalan Promos | 42s | Rare | $0.73 |
| Kumena's AwakeningRivals of Ixalan · 42 | Rivals of Ixalan | 42 | Rare | €0.34 |
| Kunoros, Hound of AthreosTheros Beyond Death Promos · 222p | Theros Beyond Death Promos | 222p | Rare | €0.51 |
| Kunoros, Hound of AthreosTheros Beyond Death Promos · 222s | Theros Beyond Death Promos | 222s | Rare | €1.00 |
| Kunoros, Hound of AthreosTheros Beyond Death · 222 | Theros Beyond Death | 222 | Rare | €0.40 |
| Kunoros, Hound of AthreosTheros Beyond Death · 341 | Theros Beyond Death | 341 | Rare | €0.77 |
| Kunoros, Hound of AthreosMagic Online Promos · 79889 | Magic Online Promos | 79889 | Rare | — |
| Kuon, Ogre Ascendant // Kuon's EssenceSaviors of Kamigawa · 78 | Saviors of Kamigawa | 78 | Rare | €0.47 |
| Kurbis, Harvest CelebrantMidnight Hunt Commander · 27 | Midnight Hunt Commander | 27 | Rare | $0.37 |
| Kurkesh, Onakke AncientMagic 2015 · 153 | Magic 2015 | 153 | Rare | $0.28 |
| Kuro, PitlordChampions of Kamigawa · 123 | Champions of Kamigawa | 123 | Rare | €0.35 |
| Kuro, PitlordDuel Decks: Divine vs. Demonic · 44 | Duel Decks: Divine vs. Demonic | 44 | Rare | €0.24 |
| Kuro, PitlordDuel Decks Anthology: Divine vs. Demonic · 44 | Duel Decks Anthology: Divine vs. Demonic | 44 | Rare | €0.42 |
| Kuro, PitlordArena Anthology 4 · 15 | Arena Anthology 4 | 15 | Rare | — |
| Kusari-GamaChampions of Kamigawa · 260 | Champions of Kamigawa | 260 | Rare | €1.21 |
| Kutzil, Malamet ExemplarSecret Lair Drop Tokens · 2782 | Secret Lair Drop Tokens | 2782 | Rare | $3.53 |
| Kutzil's FlankerThe Lost Caverns of Ixalan · 20 | The Lost Caverns of Ixalan | 20 | Rare | €0.39 |
| Kutzil's FlankerThe Lost Caverns of Ixalan · 355 | The Lost Caverns of Ixalan | 355 | Rare | €0.69 |