Ran into a random cutscene in Goug Machine City with some little sphere thing with Mustadio and his dad. I was wondering if they would ever show up again.
Oh hey that reminds me. There's an obscure Ch2 cutscene that you can find in the Brave Story's cutscene list, and nowhere else; I think it's unlocked after your first visit to Goug Machine City. It's the bit where Besrodio tells Mustadio to take the stone and run. You don't get to see it when you recruit Musty because I guess he's supposed to be mysterious, and you don't get to see it when it's unlocked because I guess the game designers figured they'd done enough flashbacks already. But it exists.
Mighty Sword techniques are indeed unevadable, although they only work if the target has equipment that they can break.
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I don't like this duchy. Now, it's an adventurer.