But in Engare’s case, every massive, crisscrossing slew of curves and lines and patterns has already been proven out by the puzzles you’ve solved. Your reward for doing well in Engare isn’t unlocking more pattern-generation options; it’s the ability to understand the incredible combination of rotations and line patterns that went into each one and how they’re all geometrically solvable thanks to their adherence to X and Y axes.

Source: Engare review: The geometry of Islamic art becomes a treasure of a game | Ars Technica

Verdict: Buy two copies; donate the second one to a school computer lab.

Main site:  http://www.engare.design/

Only $6 on Steam.  I Will be trying it out on my Steam account.