The BOSS in the wild will be spawned at any time! You change lines at the place where he appears, and wander around. Remember not to run out of his sphere of influence, so that you can find him. It is refreshed fastest in the free channel, about once every half an hour, but which map are you on? You can encounter several BOSSes by walking around a lot. If you keep fighting like this, your package will be full in less than half an hour!