Nessian Asp is a common Creature — Snake card from Theros (THS), collector number 164. Current market price: $0.04 (foil $0.25), TCGplayer market prices via Scryfall.
Reach {6}{G}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)