God of Light: Remastered

I believe this achievement is unmissable, and you should unlock it during the third chapter, the Azure Tree. During this chapter, you'll be introduced to color stones that change the color of your light beam as it passes through them. This achievement requires your level solution to involve three colors of beams on the screen (not all going into the endpoint). There are a few levels in the Azure Tree with both yellow and green stones. The third color is the standard white light. 

If you manage to finish the Azure Tree without unlocking this achievement, load up level 23 of the Azure Tree, progress through the level like normal to reach the 3-star solution, then line up both the yellow and green stones in the lower right corner so the light beam passes through the green and then the yellow stone along its way to the endpoint. Finish the level like this and the achievement should unlock.