Kunoros, Hound of Athreos is a rare Legendary Creature — Dog card from Theros Beyond Death (THB), collector number 341. Current market price: $1.21 (foil $3.41), TCGplayer market prices via Scryfall.
Vigilance, menace, lifelink Creature cards in graveyards can't enter the battlefield. Players can't cast spells from graveyards.