Apr 1553
This scenario begins right before the Kō-Sō-Sun ("Kai-Sagami-Suruga" - Takeda, Hōjō, and Imagawa) triple alliance was forged.
As key differences from S1 - Nobunaga is Here, the Nagano, Ōta, and Yūki clans have now appeared, and other daimyō have since been destroyed; the Hōjō, Takeda, Imagawa, Mori, and Ōtomo have all expanded their territory.
To that end, if historical events are enabled, the "Toishi Castle Falls" event occurs right at the scenario start, destroying the Murakami clan and adding Toishi Castle to the Takeda's already-sizable domain.
In the following months, the "Meeting at Shōtokuji", "Assembly at Zentokuji", "The Shingū Party Affair", "Relocation to Kiyosu", and "Battle of Itsukushima" events will all happen in quick succession.
In general, the major powers are expanding their influence, the speed of which is only increased by the flurry of aforementioned events.
As another note - the Honnōji Incident event very rarely occurs in this scenario; for whatever reason, an event flag usually gets broken somewhere along the line here more than in other scenarios.
Custom difficulty (basically Very Hard but with disasters OFF), Long lifespan, battle death OFF, diplomacy Normal:
Note - the writer replaced the daimyō with Kawahara Tomonobu. In this case, the clan name remained "Namioka".
The Namioka clan, descendants of the famed Kitabatake Akiie (wikipedia), Commander-in-Chief of Defense of the North behind one of the most renowned lightning-swift expeditions in Japanese history.
In Ver. 1.1.2, perhaps as an allusion to this, the clan received a unique policy that raises army march speed; all of a sudden, they're worth some serious attention.
Even before that, their high-level resource management (which was likely patterned after Akiie too) made long marches and distant conquests easy even at the game's outset. It's a remarkably well-suited strong point for the Tōhoku region, where there's quite a bit of distance between castles.
Furthermore, you start with a fair amount of gold due to your starting prestige of 150, as well as quite a few officers of high starting rank. As soon as you have the income to spare, enacting System Reform Lv.3 will be a godsend.
Namioka Tomomune, who has died by the outset of most other scenarios, is present here; his "Interfere" tactic will make battle victories by retreat route blockage vastly easier. As well, Tomonaga and Tomomune have high-ranking court positions, but since they are by default considered retired, it's not possible to retire them to increase prestige further.
There's also tribes within your territory that require appeasement a whole 11 times, so encouraging the "Appease Tribe" submission will be highly useful.
In this scenario, the alliance with the Nanbu does not exist, so you'll first have to decide whether to vassalize or fight them.
Regardless of whether you go the vassalization or conquest route, task Namioka Akinori with development of your market districts/Improve Commerce submissions. It can also be a good move to spare the Kakizaki, vassalize them, and employ them as an emigre in your council.
At the outset, if you choose to do battle with the Nanbu, continuously engage them in battles and aim to win via retreat route blockage, as mentioned above.
The first move will be to march on Ōura Castle and cycle between battles and siege. Take care of reinforcement forces the same way you tackle the main troops. Once you've taken down Ōura Castle in a siege loop, quickly turn towards Sannohe Castle and advance in the same manner. If you can avoid reinforcements coming from Kunohe Castle, head to Hiyama Castle next; if such is the case and you can set up a siege loop, take it down and proceed to the next castle. Doing this, you'll be able to quite quickly start unifying northern Tōhoku.
Additionally, timing the implementation of the Small Supply Unit Deployment policy is a bit tricky; if done too early, your food supplies will get tight. As a good benchmark, you can usually wait to enact it until after capturing Hiyama and Sannohe castles.
If things go smoothly, you should be able to unify northern Tōhoku in about two years' time; southern Tōhoku will have been unified by the Date, with whom you'll now come into conflict.
Since there are so few counties across all of Tōhoku, it's recommended to have your officers focus on settlement construction, develop counties, and implement various policies as soon as you've built up the spare funds to do so.
Regarding diplomacy, first quickly improve your relations with the Nagao - it'll be crucial to form an alliance with them before you end up as neighbors. As you expand closer to Kantō, the Hōjō may momentarily be easy potential alliance partners as well. In both clans' cases, it's extremely likely that they'll attack you the second you border them.
The Date should by now have enacted System Reform Lv.2, making a main base siege possible. A standard battle would be difficult in terms of troop strength alone; sending out 4-5 small units with Confuse trait leaders will pad your odds of victory.