Confidence:StrongSolidPlausibleTentativeSpeculative

• Hazel of the Rootbloom

  2BG

  Legendary Creature — Squirrel DruidBG

  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.
• Nature's Chosen

  G

  Enchantment — AuraG

  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.
• Whirler Rogue

  2UU

  Creature — Human Rogue ArtificerU

  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.
• Clock of Omens

  4

  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.
• Urza, Lord High Artificer

  2UU

  Legendary Creature — Human ArtificerU

  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.
• Secluded Starforge

  LandC

  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.
• Baron Helmut Zemo

  BBB

  Legendary Creature — Human Noble VillainB

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

  3

  Legendary Planeswalker — TezzeretC

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

  GWU

  Legendary Creature — Human SoldierGUW

  Both cards trigger when a creature enters the battlefield — they fire together.
• April O'Neil, Live on the Scene

  1U

  Legendary Creature — Human DetectiveU

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

  1G

  Creature — Elf ArtificerG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Prowl, Stoic Strategist // Prowl, Pursuit Vehicle

  3W

  Legendary Artifact Creature — Robot // Legendary Artifact — VehicleW

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

  1G

  Creature — Human Artificer ScoutG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Tetzin, Gnome Champion // The Golden-Gear Colossus

  URW

  Legendary Artifact Creature — Gnome // Legendary Artifact Creature — GnomeRUW

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

  2

  Artifact — BookC

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

  1UR

  Legendary Planeswalker — SaheeliRU

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

  1

  Artifact — EquipmentC

  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.).
• Romana II

  3W

  Legendary Creature — Time Lord ScientistW

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

  1GW

  Legendary Creature — Halfling AdvisorGW

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

  G

  Creature — Elf RangerG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Yoshimaru, Ever Faithful

  W

  Legendary Creature — DogW

  Both cards trigger when a creature enters the battlefield — they fire together.
• Threats Around Every Corner

  3G

  EnchantmentG

  Both cards trigger when a creature enters the battlefield — they fire together.
• Golbez, Crystal Collector

  UB

  Legendary Creature — Human WizardBU

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

  4U

  InstantU

  Intellectual Offering untaps all (or many) permanents, refreshing Grinding Station's tap activation.
• Isu the Abominable

  3UU

  Legendary Snow Creature — YetiGUW

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