I have completed the normal 150 battles, with 4 battle points each (total 600). Now I am trying to get the achievement "200 Foot Journey" which is described as "Complete 200 Battles". I do not see where the other 50 battles are located. Perhaps they become unlocked at some point? The only portion of the game that I have not explored heavily is the Crawl feature, so maybe as I delve into that more battles will become unlocked?