Fish Dude is an action game. The player is "Fish Dude" a medium size fish in a small watery area. The Laws of Nature are brutal: "eat or be eaten”. The player must eat other, smaller fishes and avoid stronger enemies: bigger fishes, and birds. When our hero, Fish Dude, eats many fish, he will become stronger and can successfully defend himself against larger fish. The player has only 3 lives. Losing them all results in a "game over".