Confidence:StrongSolidPlausibleTentativeSpeculative

• Voltaic Key

  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.
• Intellectual Offering

  4U

  InstantU

  Intellectual Offering untaps all (or many) permanents, refreshing Reckoner Bankbuster's tap activation.
• Unstoppable Plan

  2U

  EnchantmentU

  Unstoppable Plan untaps all (or many) permanents, refreshing Reckoner Bankbuster's tap activation.
• Manifold Key

  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.
• Captain of the Mists

  2U

  Creature — Human WizardU

  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.
• Sonic Screwdriver

  3

  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.
• Galvanic Key

  2

  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.
• Seedborn Muse

  3GG

  Creature — SpiritG

  Seedborn Muse untaps all (or many) permanents, refreshing Reckoner Bankbuster's tap activation.
• Unwinding Clock

  4

  ArtifactC

  Unwinding Clock untaps all (or many) permanents, refreshing Reckoner Bankbuster's tap activation.
• Innkeeper's Talent

  1G

  Enchantment — ClassG

  Counter synergy: both cards work with the same kind of counters, so their effects stack in a counters deck. Not necessarily a closed loop on its own.
• Trickster Mage

  U

  Creature — Human SpellshaperU

  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.
• Paradox Engine

  5

  Legendary ArtifactC

  Paradox Engine untaps all (or many) permanents, refreshing Reckoner Bankbuster's tap activation.
• Filigree Sages

  3U

  Artifact Creature — Vedalken WizardU

  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.
• Elder Druid

  3G

  Creature — Elf Cleric 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.
• The Pandorica

  2W

  Legendary ArtifactW

  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.
• Wizard Class

  U

  Enchantment — ClassU

  Draw pair: both cards engage with card draw. With a damage-or-draw trigger between them they form a draw engine.
• Dramatic Reversal

  1U

  InstantU

  Dramatic Reversal untaps all (or many) permanents, refreshing Reckoner Bankbuster's tap activation.
• Jenson Carthalion, Druid Exile

  GW

  Legendary Creature — Human DruidBGRUW

  Mana loop: net-positive mana cycle between the two cards.
• Grim Monolith

  2

  ArtifactC

  Mana loop: net-positive mana cycle between the two cards.
• Instrument of the Bards

  G

  Legendary ArtifactG

  Mana loop: net-positive mana cycle between the two cards.
• Thornvault Forager

  1G

  Creature — Squirrel RangerG

  Mana loop: net-positive mana cycle between the two cards.
• Intrepid Paleontologist

  1G

  Creature — Human DruidG

  Mana loop: net-positive mana cycle between the two cards.
• Fanatic of Rhonas

  1G

  Creature — Snake DruidG

  Mana loop: net-positive mana cycle between the two cards.
• Reckless Lackey

  R

  Creature — Goblin PirateR

  Mana loop: net-positive mana cycle between the two cards.
• Avatar Roku, Firebender

  3RRR

  Legendary Creature — Human AvatarR

  Mana loop: net-positive mana cycle between the two cards.