Frameless puzzle.

The difficulty of framed puzzles is mainly reflected in the edge splicing of the puzzle. Due to the limitations of the border, the edges of the puzzle are usually relatively regular, and you need to carefully identify the shape and color of the puzzle in order to assemble it correctly. In addition, framed puzzles usually have more pieces and require more time and effort to assemble.

The difficulty of frameless puzzles mainly lies in the integrity of the overall picture and the symmetry of the puzzle. Since there is no limit to the frame, frameless puzzles usually have more pieces and require higher assembly skills and patience. At the same time, in order to make the entire picture more beautiful, you need to pay attention to symmetry and color matching during the assembly process, which will also increase the difficulty.