27 cards where the text includes “undying” and the name excludes “undying beast” and the name excludes “undying flames” and the name excludes “undying rage” and the name excludes “yahenni, undying partisan”

Butcher Ghoul (Duel Decks: Blessed vs. Cursed #53)
Demonlord of Ashmouth (Avacyn Restored #96)
Endling (Modern Horizons #89)
Evernight Shade (Commander 2014 #144)
Flayer of the Hatebound (Commander 2019 #144)
Garbage Elemental (Unstable #82b)
Geralf's Messenger (Dark Ascension #63)
Geralf's Mindcrusher (Dark Ascension #37)
Hancock, Ghoulish Mayor (Fallout #45)
Haunted One (Commander Legends: Battle for Baldur's Gate #654)
Hound of Griselbrand (Avacyn Restored #141)
Howlgeist (Avacyn Restored #182)
Mikaeus, the Unhallowed (Commander Masters #173)
Nardole, Resourceful Cyborg (Doctor Who #50)
Nearheath Stalker (Dark Ascension #100)
Phyrexian Midway Bamboozle (Unfinity Sticker Sheets #18)
Pyreheart Wolf (Dark Ascension #101)
Relentless Skaabs (Duel Decks: Blessed vs. Cursed #46)
Sightless Ghoul (Dark Ascension #73)
Stormbound Geist (Dark Ascension #51)
Strangleroot Geist (Dark Ascension #127)
Treacherous Pit-Dweller (Avacyn Restored #121)
Undying Evil (Dark Ascension #77)
Vengeful Vampire (Dark Ascension #78)
Vorapede (Commander 2020 #195)
Witch-king, Sky Scourge (Tales of Middle-earth Commander #511)
Young Wolf (Dark Ascension #134)

Though this query has ended, its relics still slumber in New Argive.