Genghis Khan did not attack the Chinese dynasties until he had unified the Steppe.
But Genghis Khan situation and his situation is different.
The Song dynasty in Genghis Khan times are weak.
And even then there is still the Jin empire and Xixia to the west. And the political climate at that time is different than what he is experiencing today.
While Yan bore some similarities to the Han dynasty and shared certain historical events, it was by no means an identical counterpart.
The people, their customs, and even the flow of events had diverged from the course of history Aeryon knew.
So, even though Aeryon boldly set up this raid, he also knows there is always a possibility that he would lose.
And so, to not lose, what should he do? Examine his position and examine the position of his enemies.
Mayeux has his own plans and Aeryon also have his own plans.