It's the most prank-filled competition ever as Guy Fieri asks the judges and son Hunter to select the unappetizing whammy ingredients that the all-star competitors must use to make an appetizer and entrée. Then, Guy declares a chef swap, and the judges find themselves cooking with the whammy ingredients they chose, and Hunter discovers that he'll be competing against all-star chefs. In a final twist, Guy takes a seat at the judges' table.

Four GGG winners return to Guy Fieri's Flavortown for a chance to take another crown in one big round! They must make a winner's dinner complete with an appetizer and entrée in a non-stop hour-long battle. First, Guy flips a coin to determine whether they must shop only the odd aisles (no fresh proteins) or the even aisles (no fresh produce). After the chefs deliver their appetizers, Guy flips another coin to determine whether their entrées must include an extra item under $5 or over $20. The chef who makes the highest-scoring winner's dinner will shop the market for up to $20,000