When working on Negative World, I tested gameplay and provided feedback to improve it, as well as designed a rating system to measure two factors of each level:

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• Mechanical Difficulty (how hard it is for players to navigate the level physically)

• Conceptual Difficulty (how complex the puzzles of the level are to comprehend).

Using this rating system, the levels were re-ordered to ensure the smoothest difficulty curve possible over the course of the game.