This is story related and cannot be missed. You will earn this for completing Khargs first chapter, The First Battle. Steps outlined below:
*** Spoiler - click to reveal ***- After the opening cut scene, speak with Banjo.
- Enter your home (enter-able building right near the sword fight with Lloyd, towards the top of the map, by the locked castle gate) and enter Nafias bedroom; interact with the glowing stone on the bookshelf.
- Leave Yewbell and enter the Scrappe Plateau to the north of Yewbell. Defeat the only enemies there.
- Return to Yewbell and go to your home. Then proceed to the town square.
- Speak with Morth inside Nafias bedroom, then leave your house and speak to Zev who is behind the castle gate to the left of your house.
- Head towards the exit of the town to the southwest and speak to the "leader" of the gang next to the bar. Agree to ask Duncan about unlocking the castle gate for them. Go inside the bar and speak to Duncan (to the right sitting at a desk).
- Open the gate and progress through the castle ruins (no enemies here, exit is northeast of entrance) to the Chaos Forrest. Speak with Maru who will help you take out the Slothian and the Suskle Squirrels.
- Enter Plumb canyon and help defeat the Drakyr. Once the battle is over speak with Maru, and then speak with the Defense Corps members by the exit. This will allow you to be able to leave.
- Head to Garagne Hills. This will trigger a cut scene, and the chapter will end.