| Kishla VillageTarkir: Dragonstorm · 396 | Tarkir: Dragonstorm | 396 | Rare | €0.31 |
| KismetMasters Edition IV · 17 | Masters Edition IV | 17 | Rare | — |
| Kitchen FinksFriday Night Magic 2009 · 3 | Friday Night Magic 2009 | 3 | Rare | €1.54 |
| Kitesail LarcenistThe Lost Caverns of Ixalan · 61 | The Lost Caverns of Ixalan | 61 | Rare | €0.45 |
| Kitesail LarcenistThe Lost Caverns of Ixalan · 364 | The Lost Caverns of Ixalan | 364 | Rare | €0.57 |
| Kitesail LarcenistThe Lost Caverns of Ixalan Promos · 61p | The Lost Caverns of Ixalan Promos | 61p | Rare | €0.48 |
| Kitesail LarcenistThe Lost Caverns of Ixalan Promos · 61s | The Lost Caverns of Ixalan Promos | 61s | Rare | €1.20 |
| Kithkin BrinefarerAlchemy: Lorwyn Eclipsed · 21 | Alchemy: Lorwyn Eclipsed | 21 | Rare | — |
| KitnapBloomburrow · 53 | Bloomburrow | 53 | Rare | €0.22 |
| KitnapBloomburrow · 357 | Bloomburrow | 357 | Rare | $0.32 |
| KitnapBloomburrow Promos · 53p | Bloomburrow Promos | 53p | Rare | €0.42 |
| KitnapBloomburrow Promos · 53s | Bloomburrow Promos | 53s | Rare | $0.37 |
| Kitsune, Dragon's DaughterTeenage Mutant Ninja Turtles · 41 | Teenage Mutant Ninja Turtles | 41 | Rare | €0.18 |
| Kitsune, Dragon's DaughterTeenage Mutant Ninja Turtles · 262 | Teenage Mutant Ninja Turtles | 262 | Rare | €0.35 |
| Kitsune Mystic // Autumn-Tail, Kitsune SageChampions of Kamigawa · 28 | Champions of Kamigawa | 28 | Rare | €0.34 |
| Kitsune Mystic // Autumn-Tail, Kitsune SageSalvat 2005 · G37 | Salvat 2005 | G37 | Rare | €0.25 |
| Kitsune's TechniqueTeenage Mutant Ninja Turtles · 42 | Teenage Mutant Ninja Turtles | 42 | Rare | $0.75 |
| Kitsune's TechniqueTeenage Mutant Ninja Turtles · 229 | Teenage Mutant Ninja Turtles | 229 | Rare | $0.87 |
| Kiyomaro, First to StandSaviors of Kamigawa Promos · 18★ | Saviors of Kamigawa Promos | 18★ | Rare | €1.13 |
| Kiyomaro, First to StandSaviors of Kamigawa · 18 | Saviors of Kamigawa | 18 | Rare | €0.38 |
| Kiyomaro, First to StandMagic Online Promos · 32015 | Magic Online Promos | 32015 | Rare | — |
| Kjeldoran KnightIce Age · 36 | Ice Age | 36 | Rare | €0.95 |
| Kjeldoran OutpostAlliances · 139 | Alliances | 139 | Rare | €7.52 |
| Kjeldoran OutpostWorld Championship Decks 1997 Tokens · jk139sb | World Championship Decks 1997 Tokens | jk139sb | Rare | €4.02 |
| Kjeldoran OutpostMagic Online Promos · 23952 | Magic Online Promos | 23952 | Rare | — |
| Kjeldoran OutpostMasters Edition II · 233 | Masters Edition II | 233 | Rare | — |
| Kjeldoran OutpostVintage Masters · 301 | Vintage Masters | 301 | Rare | — |
| Kjeldoran OutpostMagic Online Promos · 43628 | Magic Online Promos | 43628 | Rare | — |
| Kjeldoran PhalanxIce Age · 37 | Ice Age | 37 | Rare | $0.93 |
| Kjeldoran Royal GuardTenth Edition · 25 | Tenth Edition | 25 | Rare | €0.18 |
| Kjeldoran Royal GuardClassic Sixth Edition · 28 | Classic Sixth Edition | 28 | Rare | €0.34 |
| Kjeldoran Royal GuardFifth Edition · 44 | Fifth Edition | 44 | Rare | €0.32 |
| Kjeldoran Royal GuardSeventh Edition · 23 | Seventh Edition | 23 | Rare | $0.26 |
| Kjeldoran Royal GuardSeventh Edition · 23★ | Seventh Edition | 23★ | Rare | $0.26 |
| Kjeldoran Royal GuardIce Age · 38 | Ice Age | 38 | Rare | $0.37 |
| Klauth's WillForgotten Realms Commander · 51 | Forgotten Realms Commander | 51 | Rare | $2.33 |
| Klauth's WillForgotten Realms Commander · 321 | Forgotten Realms Commander | 321 | Rare | €1.00 |
| Klaw, Master of SoundMarvel Super Heroes Commander · 46 | Marvel Super Heroes Commander | 46 | Rare | $0.22 |
| Klaw, Master of SoundMarvel Super Heroes Commander · 352 | Marvel Super Heroes Commander | 352 | Rare | €0.82 |
| Klement, Death AcolyteAlchemy Horizons: Baldur's Gate · 1b | Alchemy Horizons: Baldur's Gate | 1b | Rare | — |
| Klement, Knowledge AcolyteAlchemy Horizons: Baldur's Gate · 1u | Alchemy Horizons: Baldur's Gate | 1u | Rare | — |
| Klement, Life AcolyteAlchemy Horizons: Baldur's Gate · 1w | Alchemy Horizons: Baldur's Gate | 1w | Rare | — |
| Klement, Nature AcolyteAlchemy Horizons: Baldur's Gate · 1g | Alchemy Horizons: Baldur's Gate | 1g | Rare | — |
| Klement, Novice AcolyteAlchemy Horizons: Baldur's Gate · 1 | Alchemy Horizons: Baldur's Gate | 1 | Rare | — |
| Klement, Tempest AcolyteAlchemy Horizons: Baldur's Gate · 1r | Alchemy Horizons: Baldur's Gate | 1r | Rare | — |
| Knacksaw CliqueShadowmoor · 42 | Shadowmoor | 42 | Rare | €2.11 |
| Knickknack OupheWilds of Eldraine Commander · 18 | Wilds of Eldraine Commander | 18 | Rare | €0.15 |
| Knickknack OupheWilds of Eldraine Commander · 54 | Wilds of Eldraine Commander | 54 | Rare | $0.26 |
| Knife and DeathUnfinity · 77 | Unfinity | 77 | Rare | €0.12 |
| Knife and DeathUnfinity · 363 | Unfinity | 363 | Rare | €0.20 |