Nice game, kinda hard for me to get the timing right (kinda the point of the game tho)
I think if you allowed the player to mix potions (like yellow + blue = green ) or something else to flair up the game, it would increase the skillcap.
I also think having a ending menu w/ a score is important for these types of game. So you can compare w/ people & friends afterward.
Good game, & also good polish.