Fylgja is a common Enchantment — Aura card from Ice Age (ICE), collector number 26. Current market price: $0.16, TCGplayer market prices via Scryfall.
Enchant creature This Aura enters with four healing counters on it. Remove a healing counter from this Aura: Prevent the next 1 damage that would be dealt to enchanted creature this turn. {2}{W}: Put a healing counter on this Aura.