Kraul Harpooner is a uncommon Creature — Insect Warrior card from Guilds of Ravnica (GRN), collector number 136. Current market price: $0.36 (foil $1.15), TCGplayer market prices via Scryfall.
Reach Undergrowth — When this creature enters, choose up to one target creature you don't control with flying. This creature gets +X/+0 until end of turn, where X is the number of creature cards in your graveyard, then you may have this creature fight that creature.