Confidence:StrongSolidPlausibleTentativeSpeculative

• Isu the Abominable

  3UU

  Legendary Snow Creature — YetiGUW

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Isu the Abominable's enter-the-battlefield effect.
• Mirror Room // Fractured Realm

  2U5UU

  Enchantment — Room // Enchantment — RoomU

  Mirror Room makes Undergrowth Recon's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Talon Gates of Madara

  Land — GateC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Talon Gates of Madara's enter-the-battlefield effect.
• Echoing Deeps

  Land — CaveC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Echoing Deeps's enter-the-battlefield effect.
• Vesuva

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Vesuva's enter-the-battlefield effect.
• Kodama of the East Tree

  4GG

  Legendary Creature — SpiritG

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Kodama of the East Tree's enter-the-battlefield effect.
• Amareth, the Lustrous

  3GWU

  Legendary Creature — DragonGUW

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Amareth, the Lustrous's enter-the-battlefield effect.
• Petrified Hamlet

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Petrified Hamlet's enter-the-battlefield effect.
• Plaza of Harmony

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Plaza of Harmony's enter-the-battlefield effect.
• Rumble Arena

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Rumble Arena's enter-the-battlefield effect.
• Mortuary Mire

  LandB

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Mortuary Mire's enter-the-battlefield effect.
• Brokers Hideout

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Brokers Hideout's enter-the-battlefield effect.
• Cabaretti Courtyard

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Cabaretti Courtyard's enter-the-battlefield effect.
• Maestros Theater

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Maestros Theater's enter-the-battlefield effect.
• Obscura Storefront

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Obscura Storefront's enter-the-battlefield effect.
• Riveteers Overlook

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Riveteers Overlook's enter-the-battlefield effect.
• The Grey Havens

  Legendary LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing The Grey Havens's enter-the-battlefield effect.
• Aether Hub

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Aether Hub's enter-the-battlefield effect.
• Boros Garrison

  LandRW

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Boros Garrison's enter-the-battlefield effect.
• Crosis's Catacombs

  Land — LairBRU

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Crosis's Catacombs's enter-the-battlefield effect.
• Darigaaz's Caldera

  Land — LairBGR

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Darigaaz's Caldera's enter-the-battlefield effect.
• Dromar's Cavern

  Land — LairBUW

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Dromar's Cavern's enter-the-battlefield effect.
• Glacial Chasm

  LandC

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Glacial Chasm's enter-the-battlefield effect.
• Gruul Turf

  LandGR

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Gruul Turf's enter-the-battlefield effect.
• Rakdos Carnarium

  LandBR

  Undergrowth Recon returns creatures from the graveyard to the battlefield, re-firing Rakdos Carnarium's enter-the-battlefield effect.