Chandra's Regulator is a rare Legendary Artifact card from Core Set 2020 (M20), collector number 131. Current market price: $0.32 (foil $0.28), TCGplayer market prices via Scryfall.
Whenever you activate a loyalty ability of a Chandra planeswalker, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy. {1}, {T}, Discard a Mountain card or a red card: Draw a card.