Confidence:StrongSolidPlausibleTentativeSpeculative

• Keiga, the Tide Star

  5U

  Legendary Creature — Dragon SpiritU

  Synergy between the two cards.
• Chevill, Bane of Monsters

  BG

  Legendary Creature — Human RogueBG

  Kardur's Vicious Return produces damage that can kill creatures, enabling Chevill, Bane of Monsters's death-trigger or removal payoff.
• Minsc & Boo, Timeless Heroes

  2RG

  Legendary Planeswalker — MinscGR

  Kardur's Vicious Return produces damage that can kill creatures, enabling Minsc & Boo, Timeless Heroes's death-trigger or removal payoff.
• Bloodline Recollector // Ancestral Craving

  1BB

  Creature — Vampire Warlock // InstantB

  Kardur's Vicious Return produces damage that can kill creatures, enabling Bloodline Recollector's death-trigger or removal payoff.
• Banon, the Returners' Leader

  RW

  Legendary Creature — Human Cleric RebelRW

  Graveyard pair: one card brings creatures back from the graveyard repeatedly (or a creature that returns itself), and the other keeps feeding the loop — a recurring reanimator with a payoff, or a sacrifice outlet with a self-recurring creature.
• Captivating Glance

  2U

  Enchantment — AuraU

  Captivating Glance temporarily takes control of an opponent's creature, and Kardur's Vicious Return sacrifices it — the opponent loses the permanent for good.
• Court of Vantress

  2UU

  EnchantmentU

  Copy engine: one card makes a copy of a creature every turn, and the other's enter-the-battlefield effect rewards each copy. Real, repeatable value — the partner can't untap or re-enter the copier, so it never goes infinite.
• The Meathook Massacre

  XBB

  Legendary EnchantmentB

  Kardur's Vicious Return produces damage that can kill creatures, enabling The Meathook Massacre's death-trigger or removal payoff.
• Merieke Ri Berit

  WUB

  Legendary Creature — HumanBUW

  Merieke Ri Berit temporarily takes control of an opponent's creature, and Kardur's Vicious Return sacrifices it — the opponent loses the permanent for good.
• Mari, the Killing Quill

  1BB

  Legendary Creature — Vampire AssassinB

  Kardur's Vicious Return produces damage that can kill creatures, enabling Mari, the Killing Quill's death-trigger or removal payoff.
• Quest for the Gravelord

  B

  EnchantmentB

  Kardur's Vicious Return produces damage that can kill creatures, enabling Quest for the Gravelord's death-trigger or removal payoff.
• Edea, Possessed Sorceress

  2UBR

  Legendary Creature — Human WarlockBRU

  Edea, Possessed Sorceress temporarily takes control of an opponent's creature, and Kardur's Vicious Return sacrifices it — the opponent loses the permanent for good.
• Gravecrawler

  B

  Creature — ZombieB

  Graveyard pair: one card brings creatures back from the graveyard repeatedly (or a creature that returns itself), and the other keeps feeding the loop — a recurring reanimator with a payoff, or a sacrifice outlet with a self-recurring creature.
• Bequeathal

  G

  Enchantment — AuraG

  Kardur's Vicious Return produces damage that can kill creatures, enabling Bequeathal's death-trigger or removal payoff.
• Kraven the Hunter

  1BG

  Legendary Creature — Human Warrior VillainBG

  Kardur's Vicious Return produces damage that can kill creatures, enabling Kraven the Hunter's death-trigger or removal payoff.
• Varchild, Betrayer of Kjeldor

  2R

  Legendary Creature — Human KnightR

  Varchild, Betrayer of Kjeldor temporarily takes control of an opponent's creature, and Kardur's Vicious Return sacrifices it — the opponent loses the permanent for good.
• Undead Sprinter

  BR

  Creature — ZombieBR

  Graveyard pair: one card brings creatures back from the graveyard repeatedly (or a creature that returns itself), and the other keeps feeding the loop — a recurring reanimator with a payoff, or a sacrifice outlet with a self-recurring creature.
• Toshiro Umezawa

  1BB

  Legendary Creature — Human SamuraiB

  Kardur's Vicious Return produces damage that can kill creatures, enabling Toshiro Umezawa's death-trigger or removal payoff.
• Malicious Affliction

  BB

  InstantB

  Kardur's Vicious Return produces damage that can kill creatures, enabling Malicious Affliction's death-trigger or removal payoff.
• Timeline Culler

  BB

  Creature — Drix WarlockB

  Graveyard pair: one card brings creatures back from the graveyard repeatedly (or a creature that returns itself), and the other keeps feeding the loop — a recurring reanimator with a payoff, or a sacrifice outlet with a self-recurring creature.
• Enduring Renewal

  2WW

  EnchantmentW

  Kardur's Vicious Return produces damage that can kill creatures, enabling Enduring Renewal's death-trigger or removal payoff.
• Glissa, the Traitor

  BGG

  Legendary Creature — Phyrexian Zombie ElfBG

  Kardur's Vicious Return produces damage that can kill creatures, enabling Glissa, the Traitor's death-trigger or removal payoff.
• Liliana, Heretical Healer // Liliana, Defiant Necromancer

  1BB

  Legendary Creature — Human Cleric // Legendary Planeswalker — LilianaB

  Kardur's Vicious Return produces damage that can kill creatures, enabling Liliana, Heretical Healer's death-trigger or removal payoff.
• Nicol Bolas, Planeswalker

  4UBBR

  Legendary Planeswalker — BolasBRU

  Nicol Bolas, Planeswalker temporarily takes control of an opponent's creature, and Kardur's Vicious Return sacrifices it — the opponent loses the permanent for good.
• Terra, Magical Adept // Esper Terra

  1RG

  Legendary Creature — Human Wizard Warrior // Legendary Enchantment Creature — Saga WizardBGRUW

  Copy engine: one card makes a copy of a creature every turn, and the other's enter-the-battlefield effect rewards each copy. Real, repeatable value — the partner can't untap or re-enter the copier, so it never goes infinite.