This campaign is very short, covering only about 40 years of time. During this time, the Yamato clan rose from being just one of many clans struggling for domination of Japan to being the clan that dominated Japan for 800 years. The first four scenarios, from 365 - 375 AD, deal with the struggle against the Izumo clan, after which Yamato controlled the south part of Honshu, the main island of Japan. The fifth scenario, from 380 AD, deals with the domination of the clan and the island of Shikoku. The last three scenarios, from 385 - 405 AD, deal with the domination of the clan and the island of Kyushu.
Rating: Moderate (very small force)
Head SE with your hero. You will encounter an awful lot of Lion Kings and a few lions. Kill them all, unless you get bored. They may look scary, but they probably aren't a serious threat if you stay away from them.
To kill a Lion King in an automatic manner, fire one shot with your hero, then retreat until the lion stops. Repeat as necessary. It takes four hits to kill a Lion King and two for a basic lion. The only difficulty is in hitting a moving lion. Of course, if you use your entire force, it's very easy to kill the lions. Just make sure that your hero gets the first hit!
In the right corner of the map, you find a Blind Lame Priest and a House. Move the rest of your troops over here now. This will be your base of operations for the second phase of the scenario. The House data tells you that you have two more Blind Lame Priests somewhere. You don't see them yet because they are blind. It's also a bit tricky to move a wounded unit to where one of these priests can actually heal it, because they are lame. These priests are critical; you will be taking lots of damage in this scenario.
Move along the SE map edge towards the bottom corner. It is really important to not attack any enemy units if you can avoid it. It might be amusing to kill enemy villagers with impunity, but enemy combat units do respond at some point. You might actually be able to win by direct military conquest, but it will be very tedious. However, your Blind Lame Priests are positioned so that they are invisible to the enemy at the beginning, but once their combat units start moving, you can kiss your Priests good-bye. Then you will need to move very far for healing, if any still remains available.
Continue to skirt the map edge, moving along the SW side. You find your second priest just outside the Izumo city, on the SW map edge. This is a very exposed position, so don't draw any enemy units to him.
Phase three of the scenario starts when you have explored the entire eastern part of the map, outside the city walls. You now need to move your hero into the city. You will quickly annoy a catapult, so you have to draw it far out of the city and kill it there. Before you kill it, however, stand next to an enemy building or villager and watch the catapult blow things up. Whenever one of their buildings gets damaged, a villager will run over to repair it. Keep calling down the "friendly" artillery fire on the Izumo positions until they have no villagers left. Then you know that they have no economy, and no ability to produce new units. Send your hero back into the city and keep exploring. You soon attract a second catapult. Luring this one out of the city may be problematic, because it may get stuck in a wall corner near the city entrance. You may need to move your hero back and forth along the wall until the catapult blows it up and the pathfinding works again.
Lure as many enemy units out of the city as you can and kill them. Hopefully you can lure them out individually or in small groups. The Cavalry unit is actually a serious problem. It can easily kill your hero or your Cavalry unit unless you fight it with your entire force, and then it can easily kill an infantry unit. You need to lure it out alone, hit it a few times from range, attack it with your biggest units, and then bring the infantry in at the very end.
Your hero can't penetrate very far into the Izumo city because of the many Towers. You could send your Cavalry unit to explore along the river to the north part of the city. None of your infantry would survive, due to the many enemy Towers there. Your third Priest is in this area. You can enter the city from the north side, and you find the enemy leader there, but operations over there are just too dangerous.
In phase 4 of the scenario, you need to explore the inner part of the city. You will find nothing except a lot of Towers and a few units. Only your Cavalry can realistically get in there.
In phase 5 of the scenario, you kill the Izumo leader. None of your units can take him on, perhaps not even all together, except for your Cavalry, because it is the only unit that can run away from him. You will need to run in, fight him for about 5 rounds, and then run away and get healed, and you will need to repeat this about 8 times. When he is seriously wounded, you could commit the rest of your units as well. Actually, it is easy to kill the Izumu leader by attacking him with your entire force, as long as you don't mind losing some infantry units in the process.
Note: There is an easier trick for this. There is a temple just below the plateau (upon which the Izumu hero is standing). Place your archer hero adjacent to the temple such that he is between the temple and the plateau. The Izumu hero is within your range from here. Start firing arrows at him. There is a tree at the bottom of the plateau near the temple. You'll see that your hero can cross the path between the temple and this tree while the Izumu hero can not. He instead comes around the temple to reach you, all the while open to your fire. When he is about to reach you, cross the path between the tree and the temple to reach the other side. The Izumu hero will turn back and make another round of the temple to reach you again. Keep doing this a few times and you can easily kill the Izumu hero without a single scratch on your hero. This strategy is less tedious than the above one as you don't have to run 8 times to the faraway priest to get healed.