Rishkar, Peema Renegade is a rare Legendary Creature — Elf Druid card from Aether Revolt (AER), collector number 122. Current market price: $0.44 (foil $2.34), TCGplayer market prices via Scryfall.
When Rishkar enters, put a +1/+1 counter on each of up to two target creatures. Each creature you control with a counter on it has "{T}: Add {G}."