Confidence:StrongSolidPlausibleTentativeSpeculative

• Mirror Room // Fractured Realm

  2U5UU

  Enchantment — Room // Enchantment — RoomU

  Mirror Room makes Wellspring's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Phelia, Exuberant Shepherd

  1W

  Legendary Creature — DogW

  Phelia, Exuberant Shepherd blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Yuna, Hope of Spira

  3GW

  Legendary Creature — Human ClericGW

  Yuna, Hope of Spira returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• Aerial Extortionist

  3WW

  Creature — Bird SoldierW

  Aerial Extortionist exiles a permanent and lets its owner cast it again — the recast fires Wellspring's cast trigger or its enter-the-battlefield effect.
• What Must Be Done

  3WW

  SorceryW

  What Must Be Done returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• The Mind Stone

  1W

  Legendary Artifact — Infinity StoneW

  The Mind Stone blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Elrond, Moon-Reader

  2U

  Legendary Creature — Elf NobleU

  Elrond, Moon-Reader blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Temporal Tribulation

  2U

  InstantU

  Temporal Tribulation blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Tameshi, Reality Architect

  2U

  Legendary Creature — Moonfolk WizardUW

  Tameshi, Reality Architect returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• The Legend of Yangchen // Avatar Yangchen

  3WW

  Enchantment — Saga // Legendary Creature — AvatarW

  The Legend of Yangchen exiles a permanent and lets its owner cast it again — the recast fires Wellspring's cast trigger or its enter-the-battlefield effect.
• Soul Partition

  1W

  InstantW

  Soul Partition exiles a permanent and lets its owner cast it again — the recast fires Wellspring's cast trigger or its enter-the-battlefield effect.
• Appa, Steadfast Guardian

  2WW

  Legendary Creature — Bison AllyW

  Appa, Steadfast Guardian exiles a permanent and lets its owner cast it again — the recast fires Wellspring's cast trigger or its enter-the-battlefield effect.
• Teferi's Time Twist

  1U

  InstantU

  Teferi's Time Twist blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Brought Back

  WW

  InstantW

  Brought Back returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• Storm Herald

  2R

  Creature — Human ShamanR

  Storm Herald returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• Venser, Visionary Traveler

  3WU

  Legendary Planeswalker — VenserUW

  Venser, Visionary Traveler blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Starfield of Nyx

  4W

  EnchantmentW

  Starfield of Nyx returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• Balance of Terror

  2W

  Enchantment — SagaW

  Balance of Terror blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Iridescent Drake

  3U

  Creature — DrakeU

  Iridescent Drake returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• Wiccan, Rising Magician

  4U

  Legendary Creature — Mutant Warlock HeroU

  Wiccan, Rising Magician blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Silver Surfer, Cosmic Voyager

  4UU

  Legendary Creature — Alien HeroU

  Silver Surfer, Cosmic Voyager blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Venser, the Sojourner

  3WU

  Legendary Planeswalker — VenserUW

  Venser, the Sojourner blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.
• Rise to Glory

  3WB

  SorceryBW

  Rise to Glory returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• Squall, SeeD Mercenary

  2WB

  Legendary Creature — Human Knight MercenaryBW

  Squall, SeeD Mercenary returns creatures from the graveyard to the battlefield, re-firing Wellspring's enter-the-battlefield effect.
• Displacer Kitten

  3U

  Creature — Cat BeastU

  Displacer Kitten blinks (exiles and returns) a permanent, re-firing Wellspring's enter-the-battlefield effect.