22 cards where the text includes “nightmare”

Abyssal Harvester (Foundations #54)
Ancient Cellarspawn (Duskmourn: House of Horror Commander #16)
Ashiok, Nightmare Muse (Theros Beyond Death #208)
Ashiok, Nightmare Weaver (Theros #188)
Ashiok, Wicked Manipulator (Wilds of Eldraine #78)
Cacophony Unleashed (Commander Masters #730)
Chainer, Dementia Master (Commander Masters #144)
Chainer's Torment (Dominaria #82)
Chthonian Nightmare (Modern Horizons 3 #83)
Gisela, the Broken Blade (Eldritch Moon #28)
Hopeless Nightmare (Wilds of Eldraine #95)
Hunted Nightmare (Ikoria: Lair of Behemoths #92)
Kaheera, the Orphanguard (Ikoria: Lair of Behemoths #224)
Neva, Stalked by Nightmares (Wilds of Eldraine #209)
Nightmare (Welcome Deck 2017 #17)
Nightmare Shepherd (Duskmourn: House of Horror Commander #149)
Recurring Nightmare (Tempest Remastered #113)
Restless Fortress (Wilds of Eldraine #259)
Startled Awake // Persistent Nightmare (Shadows over Innistrad #88)
Startled Awake // Persistent Nightmare (Shadows over Innistrad #88)
Swimmer in Nightmares (Theros Beyond Death #275)
The Ultimate Nightmare of Wizards of the Coast® Customer Service (Unglued #53)
Umbris, Fear Manifest (Crimson Vow Commander #38)

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