Do you have xpack or original? If you have the original, then simply build an elite 16 unit army, walk in and take the province. Once you rout his initial army, follow to the center of his side of the map and rout off any reinforcements he gets. If you are playing with the xpack, it gets a bit more complicated, but is still doable, you just need more cav. The key is your tactical combat, you have to seize control. Don't expect any reinforcements that seems to be currently bugged for the offense.


Be ready with a bunch (6-10) of Shinobi to move in the province to establish control. You may have to build up multiple armies and strike multiple provinces in one turn depending on where you are. First move from the Echigo-Mutsu line would be for Kozuke-Shimotsuke-Hitatchi line, followed immediately by the Shimotsuke army taking Mushashi and the Hitatchi army grabbing Shimosa and Kazusa. Then you can take a break and rebuild on this three province front with two river provinces. Next I would take out Shinano, then sweep the south to Mimsaka with any breaks being taken in Imagawa's starting provinces. Then start sweeping the north side to establish a three province line based on Wakasa (or Echizen) to Owari. After that, you can stop and tech up or build the armies and Shinobi to sweep through the old Oda lands.