While Daybound/Nightbound has plenty of advantages, its not cleanly backwards compatible with older werewolves
Angel of Indemnity Argentum Masticore Elesh Norn Elspeth Conquers Death Gauntlets of Chaos Jalum Grifter Jihad Jinxed Ring Kiora Bests the Sea God Linvala, Shield of Sea Gate Lonis, Cryptozoologist Malignant Growth Mystic Remora Quest for Pure Flame Sheltering Ancient Slick Imitator Static Prison Summon: Bahamut Summon: Shiva Tempest Efreet Trivia Contest Varchild's War-Riders Veiled Apparition Vengeful Villagers Wall of Shards
Similarly, many decks built around set mechanics, like Mutate, Web-Slinging, or Earthbending, are fair game
You can open booster packs or use pack points to get specific cards
The concept that players were opposing planeswalkers who cast spells to summon creatures was already established, and the flavor text on these cards mentions people and places on Dominaria and elsewhere