First of all, great idea and fabulous use of the theme. I would also include the instruction to HOLD DOWN space because I thought I was casting spells, but it was only the little pre-spell, which didn’t waste any enemies. Also at first I thought I was selecting the colors and didn’t realize I had to adjust the levels of the selected colors before space bar mixed them all. (Maybe ‘Use left and right arrows to select a vial and up and down arrows to adjust the amount of the vial that goes into the potion. Hold down the space bar to mix and cast the potion.’) I think I was too focused on remembering what colors did what (and I’m not sure I got the correct cool/warm associations). It’s fun that enemies can heal too if you aren’t careful. Very sophisticated use of such a small playing field.