Confidence:StrongSolidPlausibleTentativeSpeculative

• Keiga, the Tide Star

  5U

  Legendary Creature — Dragon SpiritU

  Synergy between the two cards.
• Esper Sojourners

  WUB

  Artifact Creature — Vedalken WizardBUW

  One-directional refresh: one card can untap permanents the other wants to reuse. Not self-sustaining on its own — the untapper has to keep showing up.
• 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 Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.
• Merieke Ri Berit

  WUB

  Legendary Creature — HumanBUW

  Merieke Ri Berit temporarily takes control of an opponent's creature, and Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.
• Edea, Possessed Sorceress

  2UBR

  Legendary Creature — Human WarlockBRU

  Edea, Possessed Sorceress temporarily takes control of an opponent's creature, and Rakdos Riteknife 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.
• Varchild, Betrayer of Kjeldor

  2R

  Legendary Creature — Human KnightR

  Varchild, Betrayer of Kjeldor temporarily takes control of an opponent's creature, and Rakdos Riteknife 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.
• Copperhorn Scout

  G

  Creature — Elf ScoutG

  Copperhorn Scout untaps all (or many) permanents, refreshing Rakdos Riteknife's tap activation.
• 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.
• Garland, Royal Kidnapper

  2UB

  Legendary Creature — Human KnightBU

  Garland, Royal Kidnapper temporarily takes control of an opponent's creature, and Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.
• White Plume Adventurer

  2W

  Creature — Orc ClericW

  White Plume Adventurer untaps all (or many) permanents, refreshing Rakdos Riteknife's tap activation.
• Nicol Bolas, Planeswalker

  4UBBR

  Legendary Planeswalker — BolasBRU

  Nicol Bolas, Planeswalker temporarily takes control of an opponent's creature, and Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.
• The Beast, Deathless Prince

  2BR

  Legendary Creature — DemonBR

  The Beast, Deathless Prince temporarily takes control of an opponent's creature, and Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.
• Jorn, God of Winter // Kaldring, the Rimestaff

  2G1UB

  Legendary Snow Creature — God // Legendary Snow ArtifactBGU

  Jorn, God of Winter untaps all (or many) permanents, refreshing Rakdos Riteknife's tap activation.
• Geyadrone Dihada

  1UBR

  Legendary Planeswalker — DihadaBRU

  Geyadrone Dihada temporarily takes control of an opponent's creature, and Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.
• Jace, Ingenious Mind-Mage

  4UU

  Legendary Planeswalker — JaceU

  Jace, Ingenious Mind-Mage untaps all (or many) permanents, refreshing Rakdos Riteknife's tap activation.
• Aggravated Assault

  2R

  EnchantmentR

  Aggravated Assault untaps all (or many) permanents, refreshing Rakdos Riteknife's tap activation.
• Tenacious Underdog

  1B

  Creature — Human WarriorB

  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.
• Angrath, the Flame-Chained

  3BR

  Legendary Planeswalker — AngrathBR

  Angrath, the Flame-Chained temporarily takes control of an opponent's creature, and Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.
• Skaab Ruinator

  1UU

  Creature — Zombie HorrorU

  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.
• The Thirteenth Doctor

  1GU

  Legendary Creature — Time Lord DoctorGU

  The Thirteenth Doctor untaps all (or many) permanents, refreshing Rakdos Riteknife's tap activation.
• Veteran Beastrider

  1GW

  Creature — Human KnightGW

  Veteran Beastrider untaps all (or many) permanents, refreshing Rakdos Riteknife's tap activation.
• The Wretched

  3BB

  Creature — DemonB

  The Wretched temporarily takes control of an opponent's creature, and Rakdos Riteknife sacrifices it — the opponent loses the permanent for good.

• WithThornbite Staff2C

  Untap loop: each card untaps the other, generating arbitrary activations or mana. These two can't keep the loop going alone — add one of these to complete it:

  Baloth Prime3GAutomated Assembly Line1WGolem Foundry3Avacyn's Collar1Fishing Pole1Slayer's Plate3
  Show cards