OBTAINED: Locked inside a plain wooden chest in the Primordial Cave, very near the platform from which you meet the Patriarch. The key is on a piece of wooden scaffolding in the back of the same room of the cave, in the opposite direction. OBTAINED: Dropped by the head of the Dragon Terror Patrol, Tibus, in Dragon Cliff Castle. To fight them, complete the quest "Down the Hatch". OBTAINED: Purchased from Sam in the Shipwreck Camp on Sentinel Island. OBTAINED: Purchased from Artemas in Dragon Cliff Castle in the Orobas Fjords.