$9 lunch (save $1 with your Amigo Club card). Billed as 'The Ultimate Buffet Adventure'. 46 reviews of Fiesta Rancho Festival Buffet - Temp. Child 0-4 years free^ Friday to Sunday premium seafood buffet Adult $74.90. Monday to Thursday prawn buffet Adult $52.90 Child 5-12 years $28.90. Child 0-4 years free^ Saturday & Sunday oyster lunch Adult $50.90 Child 5-12 years $19.90. Our already affordable fare is even better when your Boarding Pass players club earns your access to the best dining discounts in Sin City, with incredible drink deals, buffet discounts and other savings that don’t require clipping coupons! Monday and Friday prawn buffet Adult $41.90 Child 5-12 years $19.90. Get the best food at an unbeatable price by making your next dinner reservations with Fiesta Rancho.