It's buy-one-get-one-free season at Mystic Buffet, the mammoth serve-yourself spread at Mystic Lake Casino Hotel (2400 Mystic Lake Blvd., Prior Lake, 952-445-9000, There are a few caveats. The offer is available Sunday, Monday, Tuesday and Thursday through Jan. 31. Both diners must be Club Mystic members (membership is free), and the deal requires a coupon, available on the casino's website.