Hopeful Eidolon is a common Enchantment Creature — Spirit card from Theros (THS), collector number 19. Current market price: $0.14 (foil $0.65), TCGplayer market prices via Scryfall.
Bestow {3}{W} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.) Lifelink (Damage dealt by this creature also causes you to gain that much life.) Enchanted creature gets +1/+1 and has lifelink.