At first it seemed I was ahead in terms of castles and power, built up Town Portal houses, but air control was only given in the 6th Dragon Utopia; by then the opponent had caught up in power. I had to go clear a spotted treasure zone where I encountered the opp with a strong mana advantage in his favor. I decided not to attack immediately, took the nearest castle and TP-ed away to rest further off, so as to grab another speed boost and an experienced workshop, and then attack on the next turn; that's how it went, although the finale happened in my main, where the opp had upgraded his giants—luckily impls with SP near 30 carried it.
Thanks for the games!
True, I shouldn't have pushed into the main, should have maneuvered further. Thanks for the game