The Ten Principles of Puzzle Design:

• make the goal of the puzzle easy to understand
• make it easy to get started
• give the player a sense of progress
• give the puzzle a sense of solvability
• increase the difficulty gradually
• have parallelism to let the player rest
• have a pyramid structure to extend the level of interest
• have hints in order to extend the level of interest
• give the answer
• perceptual shifts are double-edged swords