Confidence:StrongSolidPlausibleTentativeSpeculative

• Llanowar Druid

  1G

  Creature — Elf DruidG

  Refuel loop: one card's payoff untaps your lands, paying for the other's activation again — repeatable every turn, and often infinite.
• Palinchron

  5UU

  Creature — IllusionU

  Refuel loop: one card's payoff untaps your lands, paying for the other's activation again — repeatable every turn, and often infinite.
• Peregrine Drake

  4U

  Creature — DrakeU

  Refuel loop: one card's payoff untaps your lands, paying for the other's activation again — repeatable every turn, and often infinite.
• Great Whale

  5UU

  Creature — WhaleU

  Refuel loop: one card's payoff untaps your lands, paying for the other's activation again — repeatable every turn, and often infinite.
• Baron Helmut Zemo

  BBB

  Legendary Creature — Human Noble VillainB

  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.
• Tinybones Joins Up

  B

  Legendary EnchantmentB

  Both cards trigger when a creature enters the battlefield — they fire together.
• Chandra, Flameshaper

  5RR

  Legendary Planeswalker — ChandraR

  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.
• Spreading Plague

  4B

  EnchantmentB

  Both cards trigger when a creature enters the battlefield — they fire together.
• Season of Growth

  1G

  EnchantmentG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Kiora, Behemoth Beckoner

  2G/U

  Legendary Planeswalker — KioraGU

  Both cards trigger when a creature enters the battlefield — they fire together.
• Faramir, Steward of Gondor

  1WU

  Legendary Creature — Human NobleUW

  Both cards trigger when a creature enters the battlefield — they fire together.
• Edea, Possessed Sorceress

  2UBR

  Legendary Creature — Human WarlockBRU

  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.
• Eye of Singularity

  3W

  World EnchantmentW

  Both cards trigger when a creature enters the battlefield — they fire together.
• Chief Magistrate of Mercadia

  4RW

  Legendary Creature — Human NobleRW

  Copy chain: one card creates hasty copies of a creature whose ability or ETB the partner exploits — the canonical Kiki-Jiki / Splinter Twin pattern.
• Massimo, the Magician

  URW

  Legendary Creature — Cat WizardRUW

  Both cards trigger when a creature enters the battlefield — they fire together.
• Warden of the Grove

  2G

  Creature — HydraG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Garruk, Curse Breaker

  3GG

  Legendary Planeswalker — GarrukG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Rinoa, Angel Wing

  2W

  Legendary Creature — Human Rebel WarlockW

  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.
• Grist, Voracious Larva // Grist, the Plague Swarm

  G

  Legendary Creature — Insect // Legendary Planeswalker — GristBG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Fecund Greenshell

  3GG

  Creature — Elemental TurtleG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Lonis, Cryptozoologist

  GU

  Legendary Creature — Snake Elf ScoutGU

  Both cards trigger when a creature enters the battlefield — they fire together.
• Thassa, Deep-Dwelling

  3U

  Legendary Enchantment Creature — GodU

  Blink pair: one card can blink creatures repeatedly, and the other's ETB rewards every re-entry. Free-running only when the blink is free or refunded (Deadeye + Drake class); otherwise a repeatable value engine.
• Gladewalker Ritualist

  2G

  Creature — ShapeshifterG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Garruk's Uprising

  2G

  EnchantmentG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Sunstrike Legionnaire

  1W

  Creature — Human SoldierW

  Both cards trigger when a creature enters the battlefield — they fire together.