The very poor roads led to the late game. I had just taken full control and was preparing to double my 10 Archons, but Kirr attacked the main castle, with +20 defense against mine (and -20 to magic).
In the final, the key moment was the unexpected resurrection of the Archons, even though they had Efreet on their side: another hint for both of us. After getting the first speed, I removed the anti-magic from the ducks; otherwise, I would have had to use earth elementals.
Thanks for the game!