15 cards where the card is in the spellbook for “protean war engine”

Benalish Marshal (Game Night #8)
Blade Historian (Strixhaven: School of Mages #165)
Captivating Crew (Outlaws of Thunder Junction Commander #159)
Duelcraft Trainer (Innistrad: Midnight Hunt #16)
Falconer Adept (Core Set 2021 #18)
Manaform Hellkite (Innistrad: Crimson Vow #170)
Moonveil Regent (Innistrad: Midnight Hunt #149)
Ogre Battledriver (Duel Decks: Speed vs. Cunning #16)
Resplendent Angel (The Lost Caverns of Ixalan #32)
Seraph of Dawn (Commander Legends #44)
Serra Angel (Dominaria Remastered #25)
Serra Paragon (Dominaria United #32)
Skyship Stalker (Forgotten Realms Commander #141)
Star-Crowned Stag (Core Set 2019 #38)
Steel-Plume Marshal (Jumpstart #5)

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