Rakan and Kyara, on the lower corners of the map, aren't as threatening as
the others, and should be killed first, mainly to amass kiryoku.
As usual, your best chances against Bian and Shuu are your Bunshin-enabled
units: rise their ki to 130 and have them attack; even so, their armor has to
be very high to survive if they're hit. Do your best to lure only one of them
out of their spot, so you can deal with them one by one.