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.
• Najeela, the Blade-Blossom

  2R

  Legendary Creature — Human WarriorBGRUW

  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.
• Basri, Tomorrow's Champion

  W

  Legendary Creature — Human KnightW

  Basri, Tomorrow's Champion has cycling, and Daughter of the Deep pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Morska, Undersea Sleuth

  GWU

  Legendary Creature — Vedalken Fish DetectiveGUW

  Both cards trigger when you draw a card — they fire together.
• Unearth

  B

  SorceryB

  Unearth has cycling, and Daughter of the Deep pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Flame Blitz

  R

  EnchantmentR

  Flame Blitz has cycling, and Daughter of the Deep pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• My Precious // Allure of Power

  31B

  Legendary Artifact — Equipment // Instant — AdventureB

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

  G

  Creature — Elf ScoutG

  Copperhorn Scout untaps all (or many) permanents, refreshing Daughter of the Deep's tap activation.
• Jolted Awake

  W

  SorceryW

  Jolted Awake has cycling, and Daughter of the Deep pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Elvish Scout

  G

  Creature — Elf ScoutG

  Untap loop: each side can untap what the other taps — a genuine mutual refresh engine.
• Decree of Annihilation

  8RR

  SorceryR

  Decree of Annihilation has cycling, and Daughter of the Deep pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Zimone and Dina

  BGU

  Legendary Creature — Human DryadBGU

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

  2W

  Creature — Orc ClericW

  White Plume Adventurer untaps all (or many) permanents, refreshing Daughter of the Deep's tap activation.
• Emperor Mihail II

  1UU

  Legendary Creature — Merfolk NobleU

  Both cards produce the same kind of effect (shared token subtype).
• Jace, Ingenious Mind-Mage

  4UU

  Legendary Planeswalker — JaceU

  Jace, Ingenious Mind-Mage untaps all (or many) permanents, refreshing Daughter of the Deep's tap activation.
• Tribute to the World Tree

  GGG

  EnchantmentG

  Draw pair: both cards engage with card draw. With a damage-or-draw trigger between them they form a draw engine.
• Arcades, the Strategist

  1GWU

  Legendary Creature — Elder DragonGUW

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

  2R

  EnchantmentR

  Aggravated Assault untaps all (or many) permanents, refreshing Daughter of the Deep's tap activation.
• Bard, King of Dale

  4WU

  Legendary Creature — Human Noble ArcherUW

  One card multiplies the tokens the other creates — a token doubler pointed at a steady token source.
• Decree of Pain

  6BB

  SorceryB

  Decree of Pain has cycling, and Daughter of the Deep pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Dire Undercurrents

  3U/BU/B

  EnchantmentBU

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

  B

  Enchantment Creature — Human CitizenB

  Draw pair: both cards engage with card draw. With a damage-or-draw trigger between them they form a draw engine.
• Galadriel, Light of Valinor

  2GWU

  Legendary Creature — Elf NobleGUW

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

• Completes Ragamuffyn × Tolarian Kraken

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Bushmeat Poacher × Tolarian Kraken

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Tolarian Kraken × Cirith Ungol Patrol

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Thraxodemon × Tolarian Kraken

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Tolarian Kraken × Sprouting Goblin

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Shadowheart, Dark Justiciar × Tolarian Kraken

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Tolarian Kraken × Portcullis Vine

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Redrock Sentinel × Tolarian Kraken

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Ayara, First of Locthwain × Tolarian Kraken

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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• Completes Intruding Soulrager × Tolarian Kraken

  Untap loop: each card untaps the other, generating arbitrary activations or mana. The pair can't keep the loop going alone — this card supplies the missing piece.

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