Confidence:StrongSolidPlausibleTentativeSpeculative

• Necroplasm

  1BB

  Creature — OozeB

  Spara's Headquarters has cycling, and Necroplasm pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Magus of the Candelabra

  G

  Creature — Human WizardG

  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.
• Norman Osborn // Green Goblin

  1U1UBR

  Legendary Creature — Human Scientist Villain // Legendary Creature — Goblin Human VillainBRU

  Spara's Headquarters has cycling, and Norman Osborn pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Currency Converter

  1

  ArtifactC

  Spara's Headquarters has cycling, and Currency Converter pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Tinybones, Trinket Thief

  1B

  Legendary Creature — Skeleton RogueB

  Spara's Headquarters has cycling, and Tinybones, Trinket Thief pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Teferi, Temporal Pilgrim

  3UU

  Legendary Planeswalker — TeferiU

  Spara's Headquarters has cycling, and Teferi, Temporal Pilgrim pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Ob Nixilis Reignited

  3BB

  Legendary Planeswalker — NixilisB

  Spara's Headquarters has cycling, and Ob Nixilis Reignited pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Innocuous Researcher

  3G

  Creature — Centaur DetectiveG

  Innocuous Researcher untaps all (or many) permanents, refreshing Spara's Headquarters's tap activation.
• Red Ghost, Intangible Genius

  2UR

  Legendary Creature — Human Scientist VillainRU

  Spara's Headquarters has cycling, and Red Ghost, Intangible Genius pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Stinkweed Imp

  2B

  Creature — ImpB

  Spara's Headquarters has cycling, and Stinkweed Imp pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• The Rise of Sozin // Fire Lord Sozin

  4BB

  Enchantment — Saga // Legendary Creature — Human NobleB

  Spara's Headquarters has cycling, and The Rise of Sozin pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Sheoldred, the Apocalypse

  2BB

  Legendary Creature — Phyrexian PraetorB

  Spara's Headquarters has cycling, and Sheoldred, the Apocalypse pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Kid Loki

  U

  Legendary Creature — God Hero VillainU

  Spara's Headquarters has cycling, and Kid Loki pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Candelabra of Tawnos

  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.
• Midnight Oil

  2BB

  EnchantmentB

  Spara's Headquarters has cycling, and Midnight Oil pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Kami of the Crescent Moon

  UU

  Legendary Creature — SpiritU

  Spara's Headquarters has cycling, and Kami of the Crescent Moon pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Niv-Mizzet, Parun

  UUURRR

  Legendary Creature — Dragon WizardRU

  Spara's Headquarters has cycling, and Niv-Mizzet, Parun pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Lazotep Chancellor

  UB

  Creature — Zombie WizardBU

  Spara's Headquarters has cycling, and Lazotep Chancellor pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Jolrael, Mwonvuli Recluse

  1G

  Legendary Creature — Human DruidG

  Spara's Headquarters has cycling, and Jolrael, Mwonvuli Recluse pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Irencrag Pyromancer

  2R

  Creature — Human WizardR

  Spara's Headquarters has cycling, and Irencrag Pyromancer pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• The Raven Man

  1B

  Legendary Creature — Human WizardB

  Spara's Headquarters has cycling, and The Raven Man pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Mischievous Mystic

  1U

  Creature — Human WizardU

  Spara's Headquarters has cycling, and Mischievous Mystic pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Niv-Mizzet, the Firemind

  2UURR

  Legendary Creature — Dragon WizardRU

  Spara's Headquarters has cycling, and Niv-Mizzet, the Firemind pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Daughter of the Deep

  1U

  Creature — Merfolk NobleU

  Spara's Headquarters has cycling, and Daughter of the Deep pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.
• Insidious Roots

  BG

  EnchantmentBG

  Spara's Headquarters has cycling, and Insidious Roots pays off whenever a card is cycled — the Astral Slide / Lightning Rift engine shape.