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.
• Keiga, the Tide Star

  5U

  Legendary Creature — Dragon SpiritU

  Synergy between the two cards.
• Derevi, Empyrial Tactician

  GWU

  Legendary Creature — Bird WizardGUW

  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.
• Flash Thompson, Spider-Fan

  1W

  Legendary Creature — Human CitizenW

  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.
• Bounding Krasis

  1GU

  Creature — Fish LizardGU

  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.
• Glamermite

  2U

  Creature — Faerie RogueU

  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.
• Little Bear

  2G

  Creature — BearG

  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.
• 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.
• Village Bell-Ringer

  2W

  Creature — Human ScoutW

  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.
• Pestermite

  2U

  Creature — Faerie RogueU

  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.
• Hyrax Tower Scout

  2G

  Creature — Human ScoutG

  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.
• Giant-Sized Flying Ant

  3U

  Creature — InsectU

  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.
• Breaching Hippocamp

  3U

  Creature — Horse FishU

  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.
• Sparring Mummy

  3W

  Creature — ZombieW

  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.
• Agrus Kos, Spirit of Justice

  2RW

  Legendary Creature — Spirit DetectiveRW

  Recursion engine: one card can reanimate repeatedly (an activated ability), and the other is a creature worth bringing back again and again. Real, repeatable value — not an infinite loop on its own.
• Phlage, Titan of Fire's Fury

  1RW

  Legendary Creature — Elder GiantRW

  Recursion engine: one card can reanimate repeatedly (an activated ability), and the other is a creature worth bringing back again and again. Real, repeatable value — not an infinite loop on its own.
• Tinybones Joins Up

  B

  Legendary EnchantmentB

  Recursion engine: one card can reanimate repeatedly (an activated ability), and the other is a creature worth bringing back again and again. Real, repeatable value — not an infinite loop on its own.
• Banon, the Returners' Leader

  RW

  Legendary Creature — Human Cleric RebelRW

  Graveyard pair: one card brings creatures back from the graveyard repeatedly (or a creature that returns itself), and the other keeps feeding the loop — a recurring reanimator with a payoff, or a sacrifice outlet with a self-recurring creature.
• Captivating Glance

  2U

  Enchantment — AuraU

  Captivating Glance temporarily takes control of an opponent's creature, and Hell's Caretaker sacrifices it — the opponent loses the permanent for good.
• Solitude

  3WW

  Creature — Elemental IncarnationW

  Recursion engine: one card can reanimate repeatedly (an activated ability), and the other is a creature worth bringing back again and again. Real, repeatable value — not an infinite loop on its own.
• Uro, Titan of Nature's Wrath

  1GU

  Legendary Creature — Elder GiantGU

  Recursion engine: one card can reanimate repeatedly (an activated ability), and the other is a creature worth bringing back again and again. Real, repeatable value — not an infinite loop on its own.
• Merieke Ri Berit

  WUB

  Legendary Creature — HumanBUW

  Merieke Ri Berit temporarily takes control of an opponent's creature, and Hell's Caretaker sacrifices it — the opponent loses the permanent for good.
• Phyrexian Dreadnought

  1

  Artifact Creature — Phyrexian DreadnoughtC

  Recursion engine: one card can reanimate repeatedly (an activated ability), and the other is a creature worth bringing back again and again. Real, repeatable value — not an infinite loop on its own.

• WithThornbite Staff2C

  Untap loop: each card untaps the other, generating arbitrary activations or mana. These two can't keep the loop going alone — add one of these to complete it:

  Nurgle's RotBBaloth Prime3GThe Sibsig CeremonyBBBXathrid Necromancer2BAvacyn's Collar1Fishing Pole1
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