I exclusively use yari ashigaru and bow ashigaru (well, and generals), usually with 10 bow ashigaru and the rest generals and yari ashigaru.
Once I capture an ideal province - one with a Blacksmith, upgraded Castle, and some buildings, I replace the Yari Ashigaru with Naginata Samurai, but only as necessary. I typically have my Generals make a beeline for Ashigaru Commander skill.
Investing in building my own Naginata Samurai town would just be a waste. Building an encampment is pretty much the most I'll do, once I get the right province.
This is pretty much regardless of which clan I'm playing as. Even as Takeda or Date or Uesegi, I would still go for Naginata Samurai as the idea. Everything else is just too situational, weak, slow, etc. Would like to find a good way to incorporate a lot of Matchlocks, but hasn't worked out yet
Bookmarks