both of that kanji mean the same.
I haven't tested out that ability and didnt bother in-depth searching as to the mechanics for it. I am just assuming that the likelihood of reducing enemy def by 10% all the time is higher and have been assuming that, because I've never seen severe damage fluctuations when using the same unit with that 10% armor break ability. That said, I'm pretty sure the armor break only applies to her attack.

and yes, you're right about needing to buy that map. my 'guide' is most likely staying this way for now (meaning not much updates/add-ons), since I'm mostly on discord playing this with a couple of friends. That said, there's a difference in server between those who started on phone and those who started post-PC release version.

anyway, guess i might as well add discord link to opening post~