Sadly, it was in an alternate dimension where the Vietnamese was a split off of china.
It's somewhat true, though. China did take control over our land for about 1000 years. However, with these games, we are rewriting the history then

In our first adventure Qin Shi Huang has learned his position. This time Mao may experience the same lesson, too

The preparations for a war against Peter have been done! On the verge of turn 100, the Vietnamese finally launch their assault on St. Petersburg:
See, this is one proof showing that Le Loi is actually listening to what the readers demand

Not long ago, you have mentioned about getting out of the dead last place. Then you discussed about the first 100 turns limit. Later you requested to eliminate the Russian because their color does not fit at all. Now, you can see for yourselves that this war is an effort of ours to please them all

If you look at the right side, you may notice that Le Loi has already opened borders with Peter. During that short period, our warrior has made a lightning trip into Moscow and has observed what he needed to see. Good news for us: the Russian don't have metal, at least for now! And they haven't connected or pastured the horse, either (it's on the third ring of their capital). Thus the Vietnamese need not to afraid of a fierce retaliation in the near future. And after accomplishing his mission, that warrior is returning in time to join the attacking forces and will capture a worker from Peter in the next blink. That's called good planning, eh?

Well, actually, the declaring of Le Loi is helped by a ridiculously good luck. No, we should call it lucks because there are at least three of them. First, the worker on the quarry has just finished his work last turn

Second, the warrior near Moscow had been wandering exclusively in the area of St. Petersburg – he's just getting back to Moscow this very turn, probably because Peter is feeling intimidated by the visiting of our warrior

And thirdly, the worker sheltering in the Russian city has not moved anywhere else – he has been finished the very last turn, too

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