What a great idea for a game!
At first, I was a bit confused what I should do, then I read in the comments that you are supposed to reach the flower fields.
The notation is different from what I'm used to. For me, 1 i2 means 1 * 2i. It took me a while to understand that it's 1 + 2i. A text field that shows the latest equation would clear thing up :)
For example
(1 + 2i) * (-i) = 2 - i after the player clicked (-i).
Overall it's an amazing game and well executed. The graphics and animation look great too. Keep up the good work :)