Great Alhcemist

An important tip:

If you are close to the end, then you already know how annoyingly long the levels are, and even how frustrating it is to fail one. It will cost you some serious time.

The tip is that; once you completed the very last level, don't instantly close the game or go to the main menu, you must click on "NEXT" in order to finish the game (you will have result page with your total points) and get this achievement. I did the mistake to not click on this button, and had to repeat the whole last level once more.