Historian's Boon is a rare Enchantment card from Dominaria United Commander (DMC), collector number 21. Current market price: $2.74 (foil $2.88), TCGplayer market prices via Scryfall.
Whenever this enchantment or another nontoken enchantment you control enters, create a 1/1 white Soldier creature token. Whenever the final chapter ability of a Saga you control triggers, create a 4/4 white Angel creature token with flying and vigilance.