Nurturer Initiate is a common Creature — Elf Shaman card from Shadowmoor (SHM), collector number 124. Current market price: $0.15 (foil $1.34), TCGplayer market prices via Scryfall.
Whenever a player casts a green spell, you may pay {1}. If you do, target creature gets +1/+1 until end of turn.