Stormscale Scion is a mythic Creature — Dragon card from Tarkir: Dragonstorm (TDM), collector number 303. Current market price: $3.85 (foil $7.41), TCGplayer market prices via Scryfall.
Flying Other Dragons you control get +1/+1. Storm (When you cast this spell, copy it for each spell cast before it this turn. Copies become tokens.)