The only good Persian I can find is Esther, and neither her nor any Judean King had anything to do with what happened here that I can figure out (of course someone may come along to correct me).
While I like the ability (quite a bit, even if it is hard to read), I don't see the restriction of being played on a Persian or Judean fitting the verse, ability, or theme.
Also, in fitting with the OT cards that search for fortresses, I would restrict the search to OT fortresses.