Confidence:StrongSolidPlausibleTentativeSpeculative

• Asmodeus the Archfiend

  4BB

  Legendary Creature — Devil GodB

  Asmodeus the Archfiend bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Reanimate

  B

  SorceryB

  Reanimate puts Retriever Phoenix onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Ashiok, Nightmare Muse

  3UB

  Legendary Planeswalker — AshiokBU

  Ashiok, Nightmare Muse bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Time Wipe

  2WWU

  SorceryUW

  Time Wipe bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Mistbreath Elder

  G

  Creature — Frog WarriorG

  Mistbreath Elder bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Grave Researcher // Reanimate

  2BB

  Creature — Troll Warlock // SorceryB

  Grave Researcher puts Retriever Phoenix onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Dour Port-Mage

  1U

  Creature — Frog WizardU

  Dour Port-Mage bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Vedalken Aethermage

  1U

  Creature — Vedalken WizardU

  Vedalken Aethermage bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Chain of Vapor

  U

  InstantU

  Chain of Vapor bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Karn's Temporal Sundering

  4UU

  Legendary SorceryU

  Karn's Temporal Sundering bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Trusted Advisor

  U

  Creature — Human AdvisorU

  Trusted Advisor bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• The Eagles Are Coming!

  1W

  InstantW

  The Eagles Are Coming! bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Clutch of Currents

  U

  SorceryU

  Clutch of Currents bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Arthur, Marigold Knight

  2URW

  Legendary Creature — Mouse KnightRUW

  Arthur, Marigold Knight bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Priest of Fell Rites

  WB

  Creature — Human WarlockBW

  Priest of Fell Rites puts Retriever Phoenix onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Orzhov Charm

  WB

  InstantBW

  Orzhov Charm bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Water Whip

  UU

  Sorcery — LessonU

  Water Whip bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Mark of Eviction

  U

  Enchantment — AuraU

  Mark of Eviction bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Kaito, Dancing Shadow

  2UB

  Legendary Planeswalker — KaitoBU

  Kaito, Dancing Shadow bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Silent Departure

  U

  SorceryU

  Silent Departure bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Vapor Snag

  U

  InstantU

  Vapor Snag bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Grazilaxx, Illithid Scholar

  1UU

  Legendary Creature — HorrorU

  Grazilaxx, Illithid Scholar bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Teferi, Time Raveler

  1WU

  Legendary Planeswalker — TeferiUW

  Teferi, Time Raveler bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.
• Aerial Extortionist

  3WW

  Creature — Bird SoldierW

  Aerial Extortionist exiles a permanent and lets its owner cast it again — the recast fires Retriever Phoenix's cast trigger or its enter-the-battlefield effect.
• Scalding Viper // Steam Clean

  1R1U

  Creature — Elemental Snake // Sorcery — AdventureRU

  Scalding Viper bounces a permanent, enabling Retriever Phoenix's recast / spell-cast trigger.