So this was the plan: Remove Hatty to have a clear way to attack Qin next. All other wars in the world had ended by now though, so first I paid Caesar some techs to resume the fighting in 1715AD.
On the same year I planned to declare war on Hatty. On the other hand, I was on pleased relations with her, so why not ask her for a favor before?
She wouldn't declare war on someone unfortunately, but a trade embargo with Qin for free was nice, too. Have I mentioned how I love diplomacy? After she agreed to the embargo for free, I immediately turned around and declared war on her. I'm a real bastard...
The plan was to capture Heliopolis first, as it had dyes I was currently importing from her. Parallel to that, a second attack group would leave Toledo and invade her southern lands through the mountains towards Elephantine.
The first part of the plan, capturing Heliopolis, worked splendidly.
However, the southern attack group had to turn around immediately and withdraw to Baghdad to protect the city, as Hatty sent an invasion force of herself via boat on the first turn of the war!
I was able to deal with that threat, but I would have lost the city if I hadn't had this second attack group in this area by chance. After healing, it marched towards Elephantine as planned, though. I love city raider siege units!
Another city in the south was captured while my army in Heliopolis was busy fending off counter-attacks in the meantime, but then both attack groups were able to join again in the siege of Thebes.
Hatty's back was broken now. After Thebes, I split up the group in two again, and captured two more cities on the same turn before making peace with Hatty again, as she only had one island city (Alexandria) and a far-away city (Giza) left.
So now my frontlines were reduced considerably, and I had my back free of any surprises. Now only Saladin's buffer city stood between me and Qin, the clear AI tech leader and biggest threat to me now. Time to finish Saladin off, and then to go after Qin! I could feel that even more fun laid ahead of me.