Deflecting Palm is a rare Instant card from Khans of Tarkir Promos (PKTK), collector number 173s. Current market price: — (foil $13.21), TCGplayer market prices via Scryfall.
The next time a source of your choice would deal damage to you this turn, prevent that damage. If damage is prevented this way, Deflecting Palm deals that much damage to that source's controller.