Getting Large Armies
Using the .muchkoku. cheat, make sure you have at least one emissary and make an alliance with all of your neighbouring clans. Focusing on your territory where your daymio started off, train one full flag of EACH of the following units: Yari ashigaru, Yari samurai, Samurai archers, Yari cavalry, and Cavalry archers
(or you can train one full flag of EVERY unit type but that takes too long and the other clans have large armies themselves)
The reason for getting the alliances is to buy some time. You will lose a bit of trust with other clans but at tyhis stage you will need to betray ONE of your neighbouring clans, and then when you have defeated then, the other, and so on. Once these clans are defeated make sure you have AT LEAST two units in each territory (without breaking up your full flags) and reinforce any required lost units in your flags.
Once all this is done destroy your new neighbours one at a time and then repeat above until victory.
It is the easiest win I personally have ever won on this game.
WARNING: I have only tried this on easy and normal difficulties.
We have more cheats and tips for this game here, Shogun: Total War cheats
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