Hi! in terms of the mechanics we kind of just went with normal puzzle mechanics (buttons, moving walls, etc.) and most of the puzzle uniqueness comes from the unique movement mechanics (especially moving along slanted walls, it unlocked so many possibilities). for most levels we just started with a basic conundrum (like for one puzzle to goal is on the left and another its on the bottom ) and then each new part further restrics movement. In terms of playtesting, since there were 2 of us making the puzzles we played eachothers puzzles as a preliminary step, and then as a final sanity check I gave them to my girlfriend to see if they are beatable for an average person :)