24 cards where the name includes “nightmare”

Ashiok, Nightmare Muse (Theros Beyond Death #208)
Ashiok, Nightmare Weaver (Theros #188)
Braids, Arisen Nightmare (Dominaria United #84)
Brisela, Voice of Nightmares (Eldritch Moon #15b)
Chainer, Nightmare Adept (Modern Horizons 2 #289)
Collective Nightmare (March of the Machine #95)
Elspeth's Nightmare (Theros Beyond Death #91)
Hopeless Nightmare (Wilds of Eldraine #95)
Hunted Nightmare (Ikoria: Lair of Behemoths #92)
Neva, Stalked by Nightmares (Wilds of Eldraine #209)
Nightmare (Welcome Deck 2017 #17)
Nightmare Incursion (Eventide #40)
Nightmare Lash (Mirrodin #219)
Nightmare Shepherd (Theros Beyond Death #108)
Nightmare's Thirst (Core Set 2019 #111)
Nightmare Unmaking (New Capenna Commander #253)
Nightmare Void (Duel Decks: Izzet vs. Golgari #73)
Recurring Nightmare (Tempest Remastered #113)
Sivriss, Nightmare Speaker (Commander Legends: Battle for Baldur's Gate #148)
Startled Awake // Persistent Nightmare (Shadows over Innistrad #88)
Startled Awake // Persistent Nightmare (Shadows over Innistrad #88)
Swimmer in Nightmares (Theros Beyond Death #275)
Taken by Nightmares (Wilds of Eldraine #112)
The Ultimate Nightmare of Wizards of the Coast® Customer Service (Unglued #53)
Waking Nightmare (Modern Masters 2015 #103)

The orcs’ banner sends a clear message: “You've reached the end of this search.”