45 cards where the text includes “search your library for a card” and the colors is B

Ayara's Oathsworn (March of the Machine: The Aftermath #11)
Beseech the Mirror (Wilds of Eldraine #82)
Beseech the Queen (Planechase #19)
Bogbrew Witch (Jumpstart #211)
Bringer of the Black Dawn (Fifth Dawn #43)
Case of the Stashed Skeleton (Murders at Karlov Manor #80)
Coveted Prize (Zendikar Rising #95)
Cruel Tutor (Portal #87)
Cynical Loner (Duskmourn: House of Horror #89)
Dark Petition (Magic Origins #90)
Demonic Bargain (Innistrad: Crimson Vow #103)
Demonic Collusion (Time Spiral #103)
Demonic Tutor (Commander Masters #150)
Demon's Herald (Shards of Alara #72)
Diabolic Intent (The Brothers' War #89)
Diabolic Tutor (Commander Anthology #54)
Entomb (Dominaria Remastered #82)
Gravebreaker Lamia (Theros Beyond Death #98)
Grim Servant (Modern Horizons 3 #97)
Grim Tutor (Core Set 2021 #103)
Hoarding Broodlord (March of the Machine #110)
Illicit Shipment (Streets of New Capenna #83)
Imperial Seal (Double Masters 2022 #79)
Increasing Ambition (Dark Ascension #69)
Infernal Tutor (Ravnica Remastered #78)
Insatiable Avarice (Outlaws of Thunder Junction #91)
Liliana Vess (Duel Decks Anthology: Garruk vs. Liliana #32)
Lively Dirge (Outlaws of Thunder Junction #93)
Mastermind's Acquisition (Rivals of Ixalan #77)
Oriq Loremage (Strixhaven: School of Mages #80)
Profane Tutor (Modern Horizons 2 #97)
Razaketh's Rite (Hour of Devastation #74)
Razaketh, the Foulblooded (Commander Masters #181)
Rhystic Tutor (Prophecy #77)
Rune-Scarred Demon (Foundations #184)
Servant of the Stinger (Outlaws of Thunder Junction #105)
Sidisi, Undead Vizier (Dragons of Tarkir #120)
Smuggler Captain (Conspiracy: Take the Crown #47)
The Creation of Avacyn (Modern Horizons 3 #86)
The Cruelty of Gix (Dominaria United #87)
Urborg Panther (Mirage #150)
Vampiric Tutor (Dominaria Remastered #108)
Vile Entomber (Foundations #616)
Whisper Squad (Ikoria: Lair of Behemoths #105)
Wishclaw Talisman (Foundations #617)

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