48 cards where the text includes “flashback” and the colors ≥ U

A-Lier, Disciple of the Drowned (Innistrad: Midnight Hunt #A-59)
Alter Reality (Torment #22)
A-Phantom Carriage (Innistrad: Midnight Hunt #A-70)
Arcane Infusion (Innistrad: Midnight Hunt #210)
Archmage's Newt (Outlaws of Thunder Junction #39)
Artful Dodge (Dark Ascension #27)
Cackling Counterpart (Modern Masters 2017 #32)
Chill of Foreboding (Dark Ascension #32)
Corpse Cobble (Innistrad: Midnight Hunt #214)
Croaking Counterpart (Innistrad: Midnight Hunt #215)
Deep Analysis (Outlaws of Thunder Junction Commander #94)
Defy Gravity (Ultimate Masters #48)
Dematerialize (Odyssey #81)
Dralnu, Lich Lord (Time Spiral Remastered #251)
Dream Twist (Eternal Masters #47)
Echo of Eons (Modern Horizons #46)
Faithful Mending (Innistrad: Midnight Hunt #221)
Fervent Denial (Commander 2019 #86)
Flash of Insight (Judgment #40)
Forbidden Alchemy (Ravnica: Clue Edition #86)
Galvanic Iteration (Outlaws of Thunder Junction Commander #227)
Grasp of Phantoms (Modern Masters 2017 #41)
Hallowed Respite (Innistrad: Midnight Hunt #227)
Increasing Confusion (Dark Ascension #41)
Katilda and Lier (March of the Machine Commander #446)
Lier, Disciple of the Drowned (Innistrad: Midnight Hunt #59)
Mass Diminish (Commander 2019 #10)
Memory Deluge (Innistrad: Midnight Hunt #62)
Memory's Journey (Innistrad #66)
Mystical Teachings (Time Spiral Remastered #76)
Mystic Retrieval (Commander 2019 #90)
Otherworldly Gaze (Murders at Karlov Manor Commander #115)
Phantom Carriage (Innistrad: Midnight Hunt #70)
Quiet Speculation (Eternal Masters #68)
Rootcoil Creeper (Innistrad: Midnight Hunt #238)
Runic Repetition (Commander 2019 #94)
Saving Grasp (Dark Ascension #46)
Scour All Possibilities (Modern Horizons #67)
Secrets of the Key (Innistrad: Midnight Hunt #73)
Self-Reflection (The Lost Caverns of Ixalan #74)
Silent Departure (Eternal Masters #72)
Siphon Insight (Outlaws of Thunder Junction Commander #242)
Slickshot Lockpicker (Outlaws of Thunder Junction #67)
Snapcaster Mage (Ultimate Masters #71)
Summons of Saruman (Tales of Middle-earth Commander #70)
Think Twice (Outlaws of Thunder Junction Commander #119)
Visions of Duplicity (Midnight Hunt Commander #33)
Winterthorn Blessing (Innistrad: Midnight Hunt #251)

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