Yeah, that's the same thing I've been doing. I don't think I've used any character for more than 4 battles that guy's the one with four).
I've pretty much been ignoring everyone's EX attacks (except Lianshi's), so I probably would have missed Zhang He's meter building completely. Going to go try that out now, I think!
(Except Zhang He's a mission guy, so I guess I'll be using Zhu/Meng again. Whoops.)
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SuperNiceDog won the Guru contest. Good job.