Confidence:StrongSolidPlausibleTentativeSpeculative

• Cursed Mirror

  2R

  ArtifactR

  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.).
• Machine God's Effigy

  4

  ArtifactU

  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.).
• Saheeli, the Sun's Brilliance

  UR

  Legendary Creature — Human ArtificerRU

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

  1RW

  Legendary Creature — Human ClownRW

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

  1RR

  Legendary Creature — Human ArtificerR

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

  1R

  Legendary Creature — Elemental IllusionR

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

  2RR

  Enchantment — AuraR

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

  3R

  Legendary Creature — Human SoldierR

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

  2RRR

  Legendary Creature — Goblin ShamanR

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

  3R

  Legendary Creature — Human WarriorR

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

  2GU

  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.
• Eye of Singularity

  3W

  World EnchantmentW

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

  2G

  Creature — ShapeshifterG

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

• WithTempestra, Dame of Games1RR

  Copy chain: each card copies the other (or both copy a third), generating arbitrary copies. These two can't keep the loop going alone — add one of these to complete it:

  Sharp-Eyed Rookie1GGala Greeters1GRose Room Treasurer3RKingpin, Wilson Fisk3BGemcutter Buccaneer3RNuka-Cola Vending Machine3
  Show cards