12 cards where it’s legal in Commander and the color identity ≤ RU and the card types include “planeswalker” and the text includes “untap”

Chandra, Fire of Kaladesh // Chandra, Roaring Flame (Magic Origins #135)
Chandra, Fire of Kaladesh // Chandra, Roaring Flame (Magic Origins #135)
Jace, Ingenious Mind-Mage (Ixalan #280)
Karn, Living Legacy (Dominaria United #1)
Koth of the Hammer (Duel Decks: Venser vs. Koth #44)
Ral Zarek (Ravnica Remastered #216)
Rowan, Fearless Sparkmage (Throne of Eldraine #304)
Saheeli, Filigree Master (The Brothers' War #219)
Tamiyo, the Moon Sage (Avacyn Restored #79)
Teferi, Temporal Archmage (Commander Masters #125)
Tezzeret the Seeker (Modern Masters 2015 #62)
Tibalt, the Fiend-Blooded (Duel Decks: Sorin vs. Tibalt #41)
Zariel, Archduke of Avernus (Adventures in the Forgotten Realms #172)

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