Hallar, the Firefletcher is a uncommon Legendary Creature — Elf Archer card from Dominaria (DOM), collector number 196. Current market price: $0.18 (foil $0.34), TCGplayer market prices via Scryfall.
Trample Whenever you cast a spell, if that spell was kicked, put a +1/+1 counter on Hallar, then Hallar deals damage equal to the number of +1/+1 counters on it to each opponent.