Confidence:StrongSolidPlausibleTentativeSpeculative

• 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.
• Season of Growth

  1G

  EnchantmentG

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

  G

  Creature — Human WizardG

  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.
• Kiora, Master of the Depths

  2GU

  Legendary Planeswalker — KioraGU

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

  3G

  Creature — Centaur DetectiveG

  Innocuous Researcher untaps all (or many) permanents, refreshing Seraph Sanctuary's tap activation.
• Fiery Gambit

  2R

  SorceryR

  Fiery Gambit untaps all (or many) permanents, refreshing Seraph Sanctuary's tap activation.
• Lagrella, the Magpie

  GWU

  Legendary Creature — Human SoldierGUW

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

  4B

  EnchantmentB

  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.
• Righteous Valkyrie

  2W

  Creature — Angel ClericW

  Both cards trigger when a creature enters the battlefield — they fire together.
• Tribute to the World Tree

  GGG

  EnchantmentG

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

  1GWU

  Legendary Creature — Elder DragonGUW

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

  1

  ArtifactC

  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.
• Slash, Reptile Rampager

  3RR

  Legendary Creature — Mutant Berserker TurtleR

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

  1G

  Creature — Dinosaur EggG

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

  1W

  Creature — Phyrexian Human ClericW

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

  3B

  EnchantmentB

  Both cards trigger when a creature enters the battlefield — they fire together.
• Mirrorhall Mimic // Ghastly Mimicry

  3U

  Creature — Spirit // Enchantment — AuraU

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).
• Bishop of Wings

  WW

  Creature — Human ClericW

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

  2U

  EnchantmentU

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

  1GU

  Creature — Frog MutantGU

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

  RWB

  Enchantment — SagaBRW

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

  1RW

  EnchantmentRW

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

  1R

  Creature — Lizard RogueR

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

  2R

  Creature — DinosaurR

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