Board Thread:Questions and Answers/@comment-29523873-20160811015556/@comment-28738889-20160811015813

BB6 (Star battle in Sixth section) is by far the best place for grinding, so I would definitely say yes. If I recall, I also pulled Bane and RWW as rewards for some battles. Obviously, the cards are horrendous, but for a collector or somebody who could make use of them, I suppose it's still pretty good. So yes, definitely complete section six (if only for the ability to grind BB6).