What is the jewel really worth?
Your card gives you half the answer. The spirit’s hidden card gives the other half. Watch its trades for clues.
Buy when the jewel looks too cheap. Sell when it looks too expensive.
Your trades move the market price, never the payout — the cards already fixed that. Every trade passes through two connected markets, so larger trades become increasingly expensive. After seven turns, the hidden card is revealed and the jewel pays out.