Barbarian Ring is a uncommon Land card from Odyssey (ODY), collector number 313. Current market price: $2.82 (foil $101.20), TCGplayer market prices via Scryfall.
{T}: Add {R}. This land deals 1 damage to you. Threshold — {R}, {T}, Sacrifice this land: It deals 2 damage to any target. Activate only if there are seven or more cards in your graveyard.