I don't remember exactly what levels you should be around, but you really shouldn't have to level up that much. If you just level up occasionally you should be fine. When I played, it wasn't that hard and I didn't have to do a lot of level grinding. If you are having a little bit of trouble with the normal enemies, then I would level up a level or two, but otherwise you shouldn't have to worry that much about leveling. You should level up pretty easily by just going to where you are supposed to go.
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