Confidence:StrongSolidPlausibleTentativeSpeculative

• Intruder Alarm✓

  2U

  EnchantmentU

  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.
• Thornbite Staff✓

  2

  Kindred Artifact — Shaman EquipmentC

  Untap loop: each side can untap what the other taps — a genuine mutual refresh engine.
• Mechanized Production

  2UU

  Enchantment — AuraU

  Alternate win condition: put the wincon on ONE of the tokens the other card produces (tokens of a batch share a name — Servos, Thopters, Treasures), and every further copy counts toward the same-name total.
• 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.
• Sky Hussar

  3WU

  Creature — Human KnightUW

  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.
• Aura of Dominion

  UU

  Enchantment — AuraU

  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.
• Copperhorn Scout

  G

  Creature — Elf ScoutG

  Copperhorn Scout untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• White Plume Adventurer

  2W

  Creature — Orc ClericW

  White Plume Adventurer untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Veteran Beastrider

  1GW

  Creature — Human KnightGW

  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.
• The Thirteenth Doctor

  1GU

  Legendary Creature — Time Lord DoctorGU

  The Thirteenth Doctor untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Drumbellower

  2W

  Creature — SpiritW

  Drumbellower untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Plargg, Dean of Chaos // Augusta, Dean of Order

  1R2W

  Legendary Creature — Orc Shaman // Legendary Creature — Human ClericRW

  Plargg, Dean of Chaos untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Samut, Voice of Dissent

  3RG

  Legendary Creature — Human WarriorGRW

  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.
• Intellectual Offering

  4U

  InstantU

  Intellectual Offering untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Dazzling Theater // Prop Room

  3W2W

  Enchantment — Room // Enchantment — RoomW

  Dazzling Theater untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Formidable Speaker

  2G

  Creature — Elf DruidG

  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.
• Stone Idol Trap

  5R

  Instant — TrapR

  Both cards produce the same kind of effect (shared token subtype).
• Éomer, Marshal of Rohan

  2RR

  Legendary Creature — Human KnightR

  Éomer, Marshal of Rohan untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Saryth, the Viper's Fang

  2GG

  Legendary Creature — Human WarlockG

  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.
• Gideon, Martial Paragon

  4W

  Legendary Planeswalker — GideonW

  Gideon, Martial Paragon untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Prophet of Kruphix

  3GU

  Creature — Human WizardGU

  Prophet of Kruphix untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Unstoppable Plan

  2U

  EnchantmentU

  Unstoppable Plan untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Ivorytusk Fortress

  2WBG

  Creature — ElephantBGW

  Ivorytusk Fortress untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Jace, Ingenious Mind-Mage

  4UU

  Legendary Planeswalker — JaceU

  Jace, Ingenious Mind-Mage untaps all (or many) permanents, refreshing Jan Jansen, Chaos Crafter's tap activation.
• Dragon Man, Reformed Robot

  2WU

  Legendary Artifact Creature — Dragon RobotUW

  Recursion engine: one card can reanimate repeatedly (an activated ability, or a return that comes back once a turn), and the other is a creature worth bringing back again and again — or a creature you recast from your graveyard beside a sacrifice outlet that doesn't pay for the recast. Real, repeatable value — not an infinite loop on its own.