9 cards where the set is “rix” and the cards are exclusive Planeswalker Deck cards

Angrath, Minotaur Pirate (Rivals of Ixalan #201)
Angrath's Ambusher (Rivals of Ixalan #202)
Angrath's Fury (Rivals of Ixalan #204)
Cinder Barrens (Rivals of Ixalan #205)
Swab Goblin (Rivals of Ixalan #203)
Vampire Champion (Rivals of Ixalan #198)
Vraska, Scheming Gorgon (Rivals of Ixalan #197)
Vraska's Conquistador (Rivals of Ixalan #199)
Vraska's Scorn (Rivals of Ixalan #200)

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