You can find this request in the farm area during chapter 1.
To finish this request you will have to find and destroy the 5 blue medallions around the farm area. Here are the locations.
Blue Medallion #1. From the note, turn around and look up to your left to find it above the big barn.
Blue Medallion #2. Go down the left side of the barn where the previous medallion was. You will find another medallion behind the shrine.
Blue Medallion #3. Now backtrack towards the entrance of the farm. You will see the next medallion hanging on the small building on the left side.
Blue Medallion #4. From the previous medallion, go through the barn on your right. The next medallion will be in the building straight ahead of you.
Blue Medallion #5. Turn around and go down the right side of the barn. Then, look through the window of the barn to find the medallion.
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