TL;DR: Circularity is a decent puzzle game riddled with bugs, which ultimately lead to a lot of frustration. I would recommend it to any puzzle lover due to some pretty ingenious levels but for the rest, I'd say stay clear till the bugs are fixed.
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Circularity - Minimalistic Adventure! as its full title is given in the about text, is a minimalist puzzle game, with equal positive and negative sides to it. It claims to be a "Relaxing puzzle with interesting game mechanics [...]" but I can only attest this to be true for some of the levels, especially at the early stages.
It's important to note that the levels are not increasing in difficulty as you progress but are arbitrarily thrown in. So you will also encounter some early levels that require many attempts to get right, if you want to 100% the game achievements. And that is the biggest problem of Circularity; whereas other puzzle games adapt by adding new mechanics as you progress to spice up the gameplay (see Hook), Circularity stays the same from start to finish, leaving behind this feeling of not caring if its level 21 or level 72.
On the flip-side, there are some levels which have ingenious solutions, not seen until you try and fail a few times (to par with Zap!3 that often triggered that blank stare of disbelief at the way a puzzle was completed).
In addition, the minimalist design is quite unique and pleasing but again with the annoyance or perhaps better described peculiarity, of moving to the next level even if you haven't completed the current level. That's forcing you to wait until the next level is loaded, quit that to the main screen and re-trace which level it was, re-load it and replay it. Forcing me to always move forward the levels was extremely frustrating, negating the "relaxing" mood, especially when re-trying missed levels for the achievements. Again, it could be easily fixed if an option was added to not auto-forward.
Lastly, the bugs encountered on many levels, with circles disappearing, achievements not triggered, right down to a couple levels missing completely essential mechanics to complete (see levels 53 and 72). For a simple puzzle game, these bugs are inexcusable, especially when they seem to have been introduced at later updates/patches.
To recap:
+ Minimalist puzzle game but not an adventure
+ Interesting new idea/concept with a decent execution
+ Pleasing, unique and uncomplicated user interface
+ Some levels are very well-designed
+ Lots of levels to keep one occupied for sometime (1.5-2hrs for 100%)
+ Steam achievements and cloud saves
- More difficult levels require cat-like reflexes and a good mouse (found these impossible to complete on a laptop's touchpad)
- The UI needs improvement, adding a way to replay a level, without always moving forward to the next
- Levels difficulty is random and not incremental, detracting from the overall experience
- Too many bugs and a couple completely broken levels at the time of this review
- No steam trade cards (why?)
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PS: For 100% achievements, the broken levels such as 58, 72 etc currently require to enable the steam console and download an older, working, version of the game from the steam depot, which is an unnecessary chore.
2.0