Puzzle Age Evolution
Crystal 5

Crystal 5 is the seasons crystal, as pointed out to me by Martin Brenner and PC_Michael.  Changing its color changes the the color of the trees, simulating the changing of the seasons.  Because I found it so hard to see, I've inset a color sample from the trees in the upper right-hand corner for each image:

Initial colors: Yellow, Red, Red, Red, Red

Color = Red

Color = Yellow

Color = Green

Color = Cyan

Color = Blue

Color = Magenta