14 cards where the card types include “planeswalker” and the color identity is BU

Ashiok, Dream Render (War of the Spark #228)
Ashiok, Nightmare Muse (Theros Beyond Death #208)
Ashiok, Nightmare Weaver (Theros #188)
Ashiok, Sculptor of Fears (Theros Beyond Death #274)
Kaito, Bane of Nightmares (Duskmourn: House of Horror #220)
Kaito, Dancing Shadow (Phyrexia: All Will Be One #204)
Kaito Shizuki (Kamigawa: Neon Dynasty #226)
Sivitri, Dragon Master (Dominaria United Commander #43)
Tasha, the Witch Queen (Commander Legends: Battle for Baldur's Gate #294)
Tasha, Unholy Archmage (Alchemy Horizons: Baldur's Gate #75)
Tezzeret, Agent of Bolas (Mirrodin Besieged #97)
Tezzeret, Master of Metal (Aether Revolt #190)
Tezzeret, Master of the Bridge (Secret Lair Drop #1701)
Tezzeret the Schemer (Aether Revolt #137)

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