Ori and the Blind Forest

This is a secret area that is only accessible AFTER restoring the wind in the Forest; Nibel. It will also require the climb ability which should be unlocked by this point.

After restoring the wind, go back to the Misty Woods (in the bottom left corner of the map), which can be accessed using Sorrow's Pass. Once inside the Misty Woods, travel all the way to the left of the area. Use your new climb ability to progress up a tree, and then you'll use your feather + wind in order to reach a tree branch. Continue to the left until the achievement unlocks when you reach the ability cell.

I've made a video encompassing 8 miscellaneous achievements. Good Eye can be seen at 03:03 in the video below, which shows these 8 achievements in chronological order at their earliest opportunity in the game. You can obtain this via some skilled bash double jumping early on, but it's easier to return Misty Woods after restoring the wind so you can just use the feather to float up and over the far-left end wall to find an Ability Cell and pop the achievement.