His (Mochi's) agents in Eiganjo had told him of Konda's plan to raid the spirit world as soon as the daimyo consulted them about it. Instead of seeing this as an outrageous blasphemy like any decent kami, Mochi saw only opportunity.... Konda was intending to disrupt the natural order of things, the balance between the physical and spiritual. Such an act would have dangerous, unpredictable repercussions, and so Mochi decided that he would not only allow it, but facilitate it.
In the twenty years of strife since Konda made his raid, Mochi had time to reflect on the wisdom of his actions and their true motivations. His introspection revealed three important things: One, he did not know what to expect as a result of Konda's crime, but he was sure he could capitalize on it for his own benefit; two, if Konda succeeded it meant the oldest and most sacred laws could be broken by someone with enough will and power, which he could capitalize on for his own benefit in the long-term; and three, it was a waste of time second-guessing his own genius because he made good decisions even when he didn't have all the facts.
When the kami attacks started, Mochi knew that Konda's reign would not survive. The daimyo had done a remarkable job uniting the different people's behind him, but once he was gone they would undoubtedly fall back into petty skirmishing and tribal warfare. Mochi knew the soratami would be largely unaffected, safe in their cloud cities, but he also thought the soratami destiny was to be more than elite survivors. They were exalted beings who worshipped him, after all. If anyone was fit to rule Kamigawa, it was the moonfolk.
If he had conceived of the plan on his own beforehand, Mochi might have tried to bring Konda down or perhaps even challenge him on the field of battle... Once Konda had decided his course, however, it became unnecessary to take action in order to topple him--he had doomed himself by his rash act. It might take decades, even centuries, but eventually the spirit world would come to claim what the Daimyo had stolen. When it did, Mochi intended for the soratami to rise in Konda's place as the dominant culture in Kamigawa.
(Guardian: Saviors of Kamigawa, pp. 156-8)