Confidence:StrongSolidPlausibleTentativeSpeculative

• Season of Growth

  1G

  EnchantmentG

  Metathran Aerostat bounces a permanent, enabling Season of Growth's recast / spell-cast trigger.
• Spreading Plague

  4B

  EnchantmentB

  Metathran Aerostat bounces a permanent, enabling Spreading Plague's recast / spell-cast trigger.
• Tinybones Joins Up

  B

  Legendary EnchantmentB

  Metathran Aerostat bounces a permanent, enabling Tinybones Joins Up's recast / spell-cast trigger.
• Grist, Voracious Larva // Grist, the Plague Swarm

  G

  Legendary Creature — Insect // Legendary Planeswalker — GristBG

  Metathran Aerostat bounces a permanent, enabling Grist, Voracious Larva's recast / spell-cast trigger.
• Momo, Friendly Flier

  W

  Legendary Creature — Lemur Bat AllyW

  Metathran Aerostat bounces a permanent, enabling Momo, Friendly Flier's recast / spell-cast trigger.
• The Sibsig Ceremony

  BBB

  Legendary EnchantmentB

  Metathran Aerostat bounces a permanent, enabling The Sibsig Ceremony's recast / spell-cast trigger.
• Tribute to the World Tree

  GGG

  EnchantmentG

  Metathran Aerostat bounces a permanent, enabling Tribute to the World Tree's recast / spell-cast trigger.
• Arcades, the Strategist

  1GWU

  Legendary Creature — Elder DragonGUW

  Metathran Aerostat bounces a permanent, enabling Arcades, the Strategist's recast / spell-cast trigger.
• Dinosaur Egg

  1G

  Creature — Dinosaur EggG

  Metathran Aerostat bounces a permanent, enabling Dinosaur Egg's recast / spell-cast trigger.
• Sylvan Anthem

  GG

  EnchantmentG

  Metathran Aerostat bounces a permanent, enabling Sylvan Anthem's recast / spell-cast trigger.
• Slash, Reptile Rampager

  3RR

  Legendary Creature — Mutant Berserker TurtleR

  Metathran Aerostat bounces a permanent, enabling Slash, Reptile Rampager's recast / spell-cast trigger.
• Watcher of the Spheres

  WU

  Creature — Bird WizardUW

  Metathran Aerostat bounces a permanent, enabling Watcher of the Spheres's recast / spell-cast trigger.
• Sunstrike Legionnaire

  1W

  Creature — Human SoldierW

  Metathran Aerostat bounces a permanent, enabling Sunstrike Legionnaire's recast / spell-cast trigger.
• Dire Undercurrents

  3U/BU/B

  EnchantmentBU

  Metathran Aerostat bounces a permanent, enabling Dire Undercurrents's recast / spell-cast trigger.
• Elas il-Kor, Sadistic Pilgrim

  WB

  Legendary Creature — Phyrexian Kor ClericBW

  Metathran Aerostat bounces a permanent, enabling Elas il-Kor, Sadistic Pilgrim's recast / spell-cast trigger.
• Pollywog Prodigy

  1U

  Creature — Frog WizardU

  Metathran Aerostat bounces a permanent, enabling Pollywog Prodigy's recast / spell-cast trigger.
• Marauding Raptor

  1R

  Creature — DinosaurR

  Metathran Aerostat bounces a permanent, enabling Marauding Raptor's recast / spell-cast trigger.
• Ayara, First of Locthwain

  BBB

  Legendary Creature — Elf NobleB

  Metathran Aerostat bounces a permanent, enabling Ayara, First of Locthwain's recast / spell-cast trigger.
• Massimo, the Magician

  URW

  Legendary Creature — Cat WizardRUW

  Metathran Aerostat bounces a permanent, enabling Massimo, the Magician's recast / spell-cast trigger.
• Ray Fillet, Wave Warrior

  2U

  Legendary Creature — Fish MutantU

  Metathran Aerostat bounces a permanent, enabling Ray Fillet, Wave Warrior's recast / spell-cast trigger.
• Warleader's Call

  1RW

  EnchantmentRW

  Metathran Aerostat bounces a permanent, enabling Warleader's Call's recast / spell-cast trigger.
• Agate Instigator

  1R

  Creature — Lizard RogueR

  Metathran Aerostat bounces a permanent, enabling Agate Instigator's recast / spell-cast trigger.
• Kiora, Master of the Depths

  2GU

  Legendary Planeswalker — KioraGU

  Metathran Aerostat bounces a permanent, enabling Kiora, Master of the Depths's recast / spell-cast trigger.
• Railway Brawler

  3GG

  Creature — Rhino WarriorG

  Metathran Aerostat bounces a permanent, enabling Railway Brawler's recast / spell-cast trigger.
• Rampaging Ferocidon

  2R

  Creature — DinosaurR

  Metathran Aerostat bounces a permanent, enabling Rampaging Ferocidon's recast / spell-cast trigger.