| Sinister SeedsPhantom Darkness · 065 | Phantom Darkness | 065 | Common | €0.05 |
| Sinister Seed TokenUnlisted Printings | Unlisted Printings | — | — | €0.43 |
| Sinister SerpentYu-Gi-Oh! Worldwide Edition: Stairway to the Destined Duel promotional cards · 002 | Yu-Gi-Oh! Worldwide Edition: Stairway to the Destined Duel promotional cards | 002 | Prismatic Secret Rare | €1.54 |
| Sinister Shadow GamesDuelist Alliance · 072 | Duelist Alliance | 072 | Ultra Rare | €0.09 |
| Sinister SprocketThe Duelist Genesis · 009 | The Duelist Genesis | 009 | Super Rare | $0.69 |
| Sinister YorishiroShadow Specters · 089 | Shadow Specters | 089 | Ultra Rare | €0.11 |
| Siphon TokenUnlisted Printings | Unlisted Printings | — | — | — |
| SirenorcaLegacy of the Valiant · 041 | Legacy of the Valiant | 041 | Common | €0.07 |
| Siren Vortex of AtlantisBeyond the Brave · 016 | Beyond the Brave | 016 | Super Rare | €0.09 |
| SishunderReturn of the Duelist · 097 | Return of the Duelist | 097 | Rare | $0.22 |
| Six Samurai UnitedPhantom Darkness · 059 | Phantom Darkness | 059 | Rare | €0.11 |
| Six Scrolls of the SamuraiCrimson Crisis · 059 | Crimson Crisis | 059 | Common | €0.13 |
| Six Strike - Double AssaultRage of the Abyss · 063 | Rage of the Abyss | 063 | Common | €0.06 |
| Six Strike - Sextuple BarrageSupreme Darkness · 078 | Supreme Darkness | 078 | Common | €0.03 |
| Six Strike - Thunder BlastStorm of Ragnarok · 089 | Storm of Ragnarok | 089 | Secret Rare | €0.28 |
| Six Strike - Triple ImpactStorm of Ragnarok · 049 | Storm of Ragnarok | 049 | Common | €0.14 |
| Six Style - Dual WieldExtreme Victory · 073 | Extreme Victory | 073 | Common | €0.10 |
| Sixth SenseLegendary Collection 4: Joey's World Mega Pack · 273 | Legendary Collection 4: Joey's World Mega Pack | 273 | Common | €0.43 |
| SkelengelStarter Deck 2006 · 011 | Starter Deck 2006 | 011 | Common | €0.07 |
| SkelesaurusShadow Specters · 037 | Shadow Specters | 037 | Common | €0.06 |
| Skeletal Dragon FelgrandDimension Force · 040 | Dimension Force | 040 | Ultra Rare | €0.22 |
| SkelgonAstral Pack Five · 018 | Astral Pack Five | 018 | Short Print | €0.14 |
| Skill DrainDark Crisis · 049 | Dark Crisis | 049 | Rare | €0.18 |
| Skilled Blue MagicianSecrets of Eternity · 032 | Secrets of Eternity | 032 | Super Rare | €0.14 |
| Skilled Brown MagicianBattle of Chaos · 024 | Battle of Chaos | 024 | Common | €0.12 |
| Skilled Dark MagicianMagician's Force · 065 | Magician's Force | 065 | Super Rare | €0.09 |
| Skilled Red MagicianDimension of Chaos · 036 | Dimension of Chaos | 036 | Rare | €0.04 |
| Skilled White MagicianMagician's Force · 064 | Magician's Force | 064 | Super Rare | €0.02 |
| Skill PrisonerLegacy of the Valiant · 078 | Legacy of the Valiant | 078 | Super Rare | $0.31 |
| Skill SuccessorAncient Prophecy · 063 | Ancient Prophecy | 063 | Super Rare | €0.08 |
| SkreechGladiator's Assault · 086 | Gladiator's Assault | 086 | Secret Rare | $0.14 |
| Skull Archfiend of ChaosChaos Origins · 002 | Chaos Origins | 002 | Super Rare | €0.60 |
| Skull Archfiend of LightningDark Crisis · 073 | Dark Crisis | 073 | Ultra Rare | €0.02 |
| SkullbirdOTS Tournament Pack 2 · 022 | OTS Tournament Pack 2 | 022 | Short Print | €2.17 |
| Skull ConductorAbsolute Powerforce · 098 | Absolute Powerforce | 098 | Rare | €0.20 |
| Skull DiceYu-Gi-Oh! The Eternal Duelist Soul promotional cards · 003 | Yu-Gi-Oh! The Eternal Duelist Soul promotional cards | 003 | Prismatic Secret Rare | €0.23 |
| Skull Dog MarronSoul of the Duelist · 003 | Soul of the Duelist | 003 | Common | €0.04 |
| Skull FlameYu-Gi-Oh! 5D's Wheelie Breakers Promotional Cards · 002 | Yu-Gi-Oh! 5D's Wheelie Breakers Promotional Cards | 002 | Super Rare | €2.26 |
| Skull GuardianTournament Pack: 2nd Season · 007 | Tournament Pack: 2nd Season | 007 | Rare | €8.72 |
| Skull Guardian, Protector of the Voiceless VoicePhantom Nightmare · 037 | Phantom Nightmare | 037 | Ultra Rare | $0.63 |
| Skull InvitationPharaoh's Servant · 056 | Pharaoh's Servant | 056 | Rare | €0.06 |
| Skull KnightMetal Raiders · 123 | Metal Raiders | 123 | Common | €0.04 |
| Skull Knight #2Legacy of Darkness · 006 | Legacy of Darkness | 006 | Common | €0.20 |
| Skull KrakenGeneration Force · 006 | Generation Force | 006 | Common | €0.04 |
| Skull LairLabyrinth of Nightmare · 082 | Labyrinth of Nightmare | 082 | Common | €0.04 |
| Skull MarinerPharaoh's Servant · 092 | Pharaoh's Servant | 092 | Common | €0.06 |
| Skull-Mark LadybugInvasion of Chaos · 079 | Invasion of Chaos | 079 | Short Print | €0.05 |
| Skull MeisterStarstrike Blast · 081 | Starstrike Blast | 081 | Secret Rare | €0.10 |
| Skull Red BirdLegend of Blue Eyes White Dragon · 105 | Legend of Blue Eyes White Dragon | 105 | Common | €0.02 |
| Skull ServantLegend of Blue Eyes White Dragon · 004 | Legend of Blue Eyes White Dragon | 004 | Common | €0.07 |