There are a secret treasure on the ocean bed. Play as a famous undersea treasure hunter to discover treasure chests, pearls and many more as you avoid dangerous sea creatures. On the top of the level's screen you'll find inf concerning the amount of treasure you should collect to finish the stage.
Use Arrow Keys to control Kubus. Use Space Bar to get a treasure or open a chest. Remember to have a sufficient level of oxygen when you dive. In the screen's bottom right corner you can see a pipe showing your reserve. You can refill your air by getting to the surface or by collecting an air bubble.