Yeah, this is clearly a work in progress. The controls are not nearly as intuitive as you think. I agree with "nobody227" that you need a reset button. A tutorial would be nice.
This might seem like a good idea, but way to over even my head, and I've studied chemistry. If you make it where there is only one answer, like "most likely" groupings, that would be far better and less confusing and teach non-chemists a thing or two.
This is an abortion. It lags and clips and... just terrible. Thanks for starting this but... start over. Plot out where your going with your game, then make your code do that.
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