Harald Unites the Elves is a rare Enchantment — Saga card from Kaldheim Promos (PKHM), collector number 213s. Current market price: — (foil $1.57), TCGplayer market prices via Scryfall.
(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.) I — Mill three cards. You may put an Elf or Tyvar card from your graveyard onto the battlefield. II — Put a +1/+1 counter on each Elf you control. III — Whenever an Elf you control attacks this turn, target creature an opponent controls gets -1/-1 until end of turn.