The Light-reflection puzzle is one of several types of mysteries that you'll need to solve in Crimson Desert, and you'll come across them pretty commonly when exploring the map. The core strategy to solve these puzzles is to reflect the beam of light on specific spots. Doing so will trigger the mechanisms and allow you to proceed.
However, it can be pretty easy to get stuck if you fail to solve these puzzles. While the degree of difficulty of cracking these puzzles can be different, the core method is the same.
