Right on TimeG 5

You do not need to 3-star all puzzles to finish this achievement, you only need 1 star on each.

The real challenge of this mode is the 2nd challenge. While some of the other challenges might take a few tries, none are ridiculously difficult. Unfortunately for the mouse users, I have no advice. Keep practicing, don't forget your 1 shuffle, and hope for the best. For touchscreen users, I suggest getting a partner to play with you. This is a single-player game, so when I mention a partner, I'm referring to a live human being in the room with you, looking at the same screen, tapping along with you. This was the only way I was able to finish the 2nd challenge, and even then, it took multiple tries. I was able to lay my laptop out in tablet mode, position it between us, and we both treated the puzzle as if we were playing independently. I searched one area while the partner searched the other, and between the two of us, we were able to keep the pace of our matching high enough to barely finish off challenge 2.