You agree with point that he made alliance to fix Yan ? Or not ?
He planned to kill Gekishin hadn't changed even after knowing Renpa is going to take action or Qin losing coz it's against Renpa. But when Qin won, he didn't waste a moment and took actions immediately.
Riboku said this battle was crucial step to prepare for REAL THING. If he had planned for this step and went to Qin to form alliance than he definitely meant to plan everything beforehand.
I already said the alliance happened because he wanted to deal with the threat of Yan, which he makes very clear in his meeting with Ryo. Logically this means he'd want to taken down Yan's #1 general. But taking down Gekishin at this point had nothing to do with the Coalition:
However, after the alliance.. Qin not only conquers Sanyou, but also changes Sanyou's name. Which as the narrator pointed out was a declaration of war to the entire continent.
After this we see Riboku looking at the map of China and looking at Sanyou:
^^^ This is when Riboku had started forming the plans for the Coalition. The battle against Yan from here on out was for him to gain prestige, hence why he wanted to win the battle in an overwhelming way:
Yes he was gonna fight the Yan either way, however, the reasoning for fighting the Yan pre-Sanyou & post-Sanyou are completely different.
Which is why we're told through Ordo that Riboku set out to form the coalition after the events that took place at Sanyou.
Qin -> Declared war on China with renaming Sanyou
Riboku -> Decided to reply back with the Coalition
If SHK doesn't pull the stunt with Sanyou, then Riboku would not have done the coalition army, as there was no need for it.
