49 cards where the colors is U and the set is “m20”

Aether Gust (Core Set 2020 #42)
Agent of Treachery (Core Set 2020 #43)
Air Elemental (Core Set 2020 #44)
Anticipate (Core Set 2020 #45)
Atemsis, All-Seeing (Core Set 2020 #46)
Befuddle (Core Set 2020 #47)
Bone to Ash (Core Set 2020 #48)
Boreal Elemental (Core Set 2020 #49)
Brineborn Cutthroat (Core Set 2020 #50)
Captivating Gyre (Core Set 2020 #51)
Cavalier of Gales (Core Set 2020 #52)
Celestial Messenger (Core Set 2020 #287)
Cerulean Drake (Core Set 2020 #53)
Cloudkin Seer (Core Set 2020 #54)
Convolute (Core Set 2020 #55)
Coral Merfolk (Core Set 2020 #315)
Drawn from Dreams (Core Set 2020 #56)
Dungeon Geists (Core Set 2020 #57)
Faerie Miscreant (Core Set 2020 #58)
Flood of Tears (Core Set 2020 #59)
Fortress Crab (Core Set 2020 #60)
Frilled Sea Serpent (Core Set 2020 #61)
Frost Lynx (Core Set 2020 #62)
Hard Cover (Core Set 2020 #63)
Leyline of Anticipation (Core Set 2020 #64)
Masterful Replication (Core Set 2020 #65)
Metropolis Sprite (Core Set 2020 #66)
Moat Piranhas (Core Set 2020 #67)
Mu Yanling, Celestial Wind (Core Set 2020 #286)
Mu Yanling, Sky Dancer (Core Set 2020 #68)
Negate (Core Set 2020 #69)
Octoprophet (Core Set 2020 #70)
Phantom Warrior (Core Set 2020 #316)
Portal of Sanctuary (Core Set 2020 #71)
Renowned Weaponsmith (Core Set 2020 #72)
Riddlemaster Sphinx (Core Set 2020 #317)
Sage's Row Denizen (Core Set 2020 #73)
Scholar of the Ages (Core Set 2020 #74)
Sleep Paralysis (Core Set 2020 #75)
Snapping Drake (Core Set 2020 #318)
Spectral Sailor (Core Set 2020 #76)
Tale's End (Core Set 2020 #77)
Unsummon (Core Set 2020 #78)
Warden of Evos Isle (Core Set 2020 #79)
Waterkin Shaman (Core Set 2020 #288)
Winged Words (Core Set 2020 #80)
Yanling's Harbinger (Core Set 2020 #289)
Yarok's Wavecrasher (Core Set 2020 #81)
Zephyr Charge (Core Set 2020 #82)

In the blink of an eye, they strode from deep snow to the end of this search.