Different puzzle piece shapes significantly affect the difficulty of a jigsaw puzzle in various ways:
Unique vs. Uniform Shapes:
Unique Shapes: Puzzles with unique, irregularly shaped pieces are typically easier because each piece is distinct and can only fit in one place. The unique contours and edges serve as strong visual cues for placement.
Uniform Shapes: Puzzles with more uniform, similarly shaped pieces (e.g., standard g…
Source: How do different puzzle piece shapes affect the difficulty of a jigsaw puzzle?