Nahiri's Wrath is a mythic Sorcery card from Eldritch Moon (EMN), collector number 137. Current market price: $0.38 (foil $1.20), TCGplayer market prices via Scryfall.
As an additional cost to cast this spell, discard X cards. Nahiri's Wrath deals damage equal to the total mana value of the discarded cards to each of up to X target creatures and/or planeswalkers.