This is the best Total War game ever made, along with the expansion. The only thing that should be improved is the diplomacy, could be a perfect game if it worked better.
You could fight incredible medieval fights and with the expansion, even experience firearms. Each faction has it's bonuses, agents of many kinds, you could send units without generals to defend, attack, reinforce....
Always loved defending a castle here against armies 3x times higher with rains of samurai arrows.