Following suggestion from a coworker, I went and beat FF6, using only Setzer, Celes, and Edgar.
I am reusing the same state with 40 hours of leveling up after getting Falcon airship, and also with the Warring Triad already defeated, so not quite the same spirit as what Guy had intended. Since Celes can cast Ultima almost nonstop, Kefka didn't really have a chance this time either, but he did manage to do some damage.
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