Use the mouse to select three pieces that together form a set of triplets. The pieces in a triplet must either be identical or have completely different characteristics such as shape, color, size, or count. For example, a set of a blue triangle, blue circle, and blue square would form a triplet as they are all blue and have different shapes, but a set of a green circle, yellow circle, and blue triangle would not be a triplet as the shapes are not all identical or all different. Find all the unique triplet sets to complete the level."