Stack the cubes with the same pictures by clicking first on one, then on the second. The pictures depict whales, snails, crocodiles, hares, lions and deer. On the left, by clicking on the yellow light, you can see a hint, or change the arrangement of the cubes. On the right is the timeline. Hurry up to get three stars. When the cubes overlap each other, the bottom one cannot be reached. First you have to remove the top. Forward!