You will trigger this by hitting 3 gold coins on the reel. The classic version allows you to choose one of the five koi - this will let you know where the slot's title comes from! Each of the five koi looks the same, but with a different colored background. Your first choice is to have 25 free games, each of which will see any victory using the Koi wild symbol multiplied by 2x, 3x or 5x.

The Deluxe Edition actually has seven Koi instead of 5. All five options in the classic game are still available, but you will find two more options. The first one saw you offer the opportunity to play only 6 free games, the multiplier here is the largest - 15 times. 30x or 40x.