43 cards where the illustration contains “purple-sky”

Angel of the Ruins (Commander 2021 #11)
Archpriest of Shadows (March of the Machine #89)
Banshee's Blade (Mirrodin #144)
Bloodcrazed Goblin (Magic 2011 #125)
Burst of Speed (Magic 2010 #129)
Candlelight Vigil (Guilds of Ravnica #3)
Citanul Centaurs (Urza's Saga #243)
Cobalt Golem (Mirrodin #157)
Crazed Armodon (Tempest #220)
Cryptolith Fragment // Aurora of Emrakul (Eldritch Moon #193)
Cryptolith Fragment // Aurora of Emrakul (Eldritch Moon #193)
Dazzling Sphinx (Commander 2021 #25)
Empyrial Storm (Commander 2018 #2)
Ethereal Valkyrie (Kaldheim Commander #16)
Fire Ants (Urza's Saga #187)
Foothill Guide (Onslaught #29)
Higure, the Still Wind (Betrayers of Kamigawa #37)
Honey Mammoth (Ikoria: Lair of Behemoths #158)
Indomitable Archangel (Scars of Mirrodin #11)
Keen Duelist (Commander 2021 #42)
Lava Axe (Urza's Legacy #84)
Mana Geyser (Fifth Dawn #75)
Marker Beetles (Urza's Destiny #112)
Mindwrack Liege (Eventide #104)
Mirri the Cursed (Time Spiral Remastered #125)
Monastery Swiftspear (Khans of Tarkir #118)
Mystic Confluence (Commander 2015 #14)
Persist (Modern Horizons 2 #96)
Rare-B-Gone (Unhinged #119)
Resolute Archangel (Magic 2015 Promos #28)
Righteousness (Tenth Edition #36)
Searing Meditation (Ravnica: City of Guilds #226)
Selfless Savior (Core Set 2021 #36)
Serendib Efreet (From the Vault: Exiled #11)
Silumgar, the Drifting Death (Commander 2017 #194)
Soul Manipulation (Alara Reborn #29)
Spirit Cairn (Judgment #26)
Steal Artifact (Seventh Edition #99)
Thunderous Might (Born of the Gods #114)
Ugin, the Ineffable (War of the Spark #2)
Unyaro Bee Sting (Mirage #250)
Vesuva (Time Spiral #281)
Wind Drake (Portal #77)
Wintermoon Mesa (Prophecy #143)

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