work on your mechanics a bit
The basic idea of the game seems interesting and good (there aren't many pure reaction-based games online). The first time I played it, I didn't bother reading the controls. Took me a few lives to realise I needed to click, but it was easy to pick up, thanks to your clean presentation.
You did make a small typo in the instructions.
The mechanics seem overly reliant on luck for my tastes - as the positions are randomly spaced, we can lose due to a circle popping up right next to the 'enemy', then maybe another pops up right beside it, making us lose a few lives in a row. Maybe the enemy could be reset each time?
The rankings seem to be totally messed up. Game 1, I got 7pts - A. Then I got 27pts - E. I played a few more times, to see how the rankings worked and it just seemed a bit random.
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More reaction-based games are a good idea, but you need to work on your mechanics a bit (and also maybe tweak the presentation further).
2/5