Achievement unlocks at the end of Episode 1 Chapter 6.
In Chapter 6, you have to:
Create a bow, then an arrow, or a fishing rod.
Read the book in the library.
Place amulet on the pedestal.
Hit switches to activate all five lights.
Decide whether to go find Magnus or Ellegaard.
For the switches, you need to press the first, fifth, and then third switches.
If you need additional help, please refer to the video walkthrough of the whole chapter:
Credit to Norcda Childa.