Insight

tl;dr: Play Understand first.

Insight is not entirely different from Understand — both share a minimalist style and a naming convention of choosing un-googleable titles. Compared to Understand, Insight leans heavier into testing your spatial reasoning. Insight is not executed as well: it's more difficult to experiment in Insight, since the game often fails to indicate whether you've broken a certain rule or not — unless your solution happens to satisfy a different rule first.

Insight doesn’t always test your understanding effectively. I sometimes reached the final level of a set with only a vague guess about how some of the rules were meant to work, even though I hadn't resorted to bruteforcing any of the solutions. It’s disheartening to find out that my assumptions were wrong all along after I've spent quite a while chasing a solution I thought should have totally worked. Sometimes solutions don’t count for reasons that feel arbitrary — like when your line turns at an already existing corner. If that’s never allowed, it shouldn't be possible to do so in the first place.

Nevertheless, the parts that do make sense are still very enjoyable (and there are plenty of them!). Given the low price and the generous number of levels, I still recommend the game — but only if you’ve already played and thoroughly enjoyed Understand.

gets pretty hard! but surprisingly fun. One of the better times I've had with one of these "rule discovery" type puzzle games.

A few mechanics I found really obscure, but the hint discussion thread was enough help to get unstuck. Overall though I could have the promised Insights on what to do, and on how to do it, given some time and taking some breaks. Recommended if you played games like Undertstand (which is the most similar), the Witness or Taiji and enjoyed what they do with rule discovery.